Add solution for 2016 Day 19

- Fix Md5 algorithm

.clang-format

@@ -81,7 +81,7 @@ AllowShortEnumsOnASingleLine: true
 AllowShortFunctionsOnASingleLine: false
 AllowShortIfStatementsOnASingleLine: Never
 AllowShortLambdasOnASingleLine: All
-AllowShortLoopsOnASingleLine: true
+AllowShortLoopsOnASingleLine: false
 AllowShortNamespacesOnASingleLine: false
 AlwaysBreakAfterDefinitionReturnType: None
 AlwaysBreakBeforeMultilineStrings: true

res/2016/day01/test_input.txt

@@ -0,0 +1 @@
+R8, R4, R4, R8

res/2016/day02/test_input.txt

@@ -0,0 +1,4 @@
+ULL
+RRDDD
+LURDL
+UUUUD

res/2016/day03/test_input.txt

@@ -0,0 +1,3 @@
+5 10 25
+11 15 25
+8 25 20

res/2016/day04/test_input.txt

@@ -0,0 +1,4 @@
+aaaaa-bbb-z-y-x-123[abxyz]
+a-b-c-d-e-f-g-h-987[abcde]
+not-a-real-room-404[oarel]
+totally-real-room-200[decoy]

res/2016/day05/test_input.txt

@@ -0,0 +1 @@
+abc

res/2016/day06/test_input.txt

@@ -0,0 +1,16 @@
+eedadn
+drvtee
+eandsr
+raavrd
+atevrs
+tsrnev
+sdttsa
+rasrtv
+nssdts
+ntnada
+svetve
+tesnvt
+vntsnd
+vrdear
+dvrsen
+enarar

res/2016/day07/test_input.txt

@@ -0,0 +1,8 @@
+abba[mnop]qrst
+abcd[bddb]xyyx
+aaaa[qwer]tyui
+ioxxoj[asdfgh]zxcvbn
+aba[bab]xyz
+xyx[xyx]xyx
+aaa[kek]eke
+zazbz[bzb]cdb

res/2016/day08/test_input.txt

@@ -0,0 +1,4 @@
+rect 3x2
+rotate column x=1 by 1
+rotate row y=0 by 4
+rotate column x=1 by 1

res/2016/day09/test_input.txt

@@ -0,0 +1 @@
+X(8x2)(3x3)ABCY

res/2016/day10/test_input.txt

@@ -0,0 +1,6 @@
+value 5 goes to bot 2
+bot 2 gives low to bot 1 and high to bot 0
+value 3 goes to bot 1
+bot 1 gives low to output 1 and high to bot 0
+bot 0 gives low to output 2 and high to output 0
+value 2 goes to bot 2

res/2016/day11/test_input.txt

@@ -0,0 +1,4 @@
+The first floor contains a hydrogen-compatible microchip and a lithium-compatible microchip.
+The second floor contains a hydrogen generator.
+The third floor contains a lithium generator.
+The fourth floor contains nothing relevant.

res/2016/day12/test_input.txt

@@ -0,0 +1,6 @@
+cpy 41 a
+inc a
+inc a
+dec a
+jnz a 2
+dec a

res/2016/day13/test_input.txt

@@ -0,0 +1 @@
+10

res/2016/day14/test_input.txt

@@ -0,0 +1 @@
+abc

res/2016/day15/test_input.txt

@@ -0,0 +1,3 @@
+Disc #1 has 5 positions; at time=0, it is at position 4.
+Disc #2 has 2 positions; at time=0, it is at position 1.
+Disc #2 has 3 positions; at time=0, it is at position 2.

res/2016/day16/test_input.txt

@@ -0,0 +1 @@
+10000

res/2016/day17/test_input.txt

@@ -0,0 +1 @@
+ulqzkmiv

res/2016/day18/test_input.txt

@@ -0,0 +1 @@
+.^^.^.^^^^

res/2016/day19/test_input.txt

@@ -0,0 +1 @@
+5

src/2016/Day01.cpp

@@ -0,0 +1,73 @@
+#include "common/aoc.h"
+
+namespace y2016::day01
+{
+  struct Move
+  {
+    char r;
+    int count;
+  };
+
+  REGISTER_DAY(2016, Day01, std::vector<Move>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day01, ExampleInput, 1, 8);
+  REGISTER_TEST(2016, Day01, Input, 1, 271);
+  REGISTER_TEST_EXAMPLE(2016, Day01, ExampleInput, 2, 4);
+  REGISTER_TEST(2016, Day01, Input, 2, 153);
+
+  READ_INPUT(input)
+  {
+    std::vector<Move> vec;
+    std::string str;
+    while (getline(input, str, ' '))
+    {
+      Move move;
+      move.r = str[0];
+      move.count = std::strtol(&str[1], nullptr, 10);
+      vec.emplace_back(move);
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    Index2D dir{1, 0};
+    Index2D pos{0, 0};
+    for (int i = 0; i < input.size(); i++)
+    {
+      if (input[i].r == 'R')
+        dir.RotateCW();
+      else
+        dir.RotateCCW();
+
+      pos = pos + dir * input[i].count;
+    }
+    return Helper::ManhattanDistance(pos, Index2D{0, 0});
+  }
+
+  OUTPUT2(input)
+  {
+    Index2D dir{1, 0};
+    Index2D pos{0, 0};
+    std::set<Index2D> visited;
+    visited.emplace(pos);
+    for (int i = 0; i < input.size(); i++)
+    {
+      if (input[i].r == 'R')
+        dir.RotateCW();
+      else
+        dir.RotateCCW();
+
+      for (int j = 0; j < input[i].count; j++)
+      {
+        pos = pos + dir;
+        if (visited.count(pos) != 0)
+        {
+          return Helper::ManhattanDistance(pos, Index2D{0, 0});
+        }
+        visited.emplace(pos);
+      }
+    }
+    return 0;
+  }
+}

src/2016/Day02.cpp

@@ -0,0 +1,126 @@
+#include "common/aoc.h"
+
+namespace y2016::day02
+{
+  REGISTER_DAY(2016, Day02, std::vector<std::string>, std::string);
+
+  REGISTER_TEST_EXAMPLE(2016, Day02, ExampleInput, 1, "1985");
+  REGISTER_TEST(2016, Day02, Input, 1, "14894");
+  REGISTER_TEST_EXAMPLE(2016, Day02, ExampleInput, 2, "5DB3");
+  REGISTER_TEST(2016, Day02, Input, 2, "26B96");
+
+  READ_INPUT(input)
+  {
+    std::vector<std::string> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+      vec.emplace_back(str);
+    }
+    return vec;
+  }
+
+  char IndexToChar1(Index2D index)
+  {
+    return (index.x + index.y * 3) + '1';
+  }
+
+  char IndexToChar2(Index2D index)
+  {
+    if (index.y == 0)
+      return '1';
+    if (index.y == 1)
+      return '2' + index.x - 1;
+    if (index.y == 2)
+      return '5' + index.x;
+    if (index.y == 3)
+      return 'A' + index.x - 1;
+    if (index.y == 4)
+      return 'D';
+    return 'X';
+  }
+
+  void ClampX(Index2D& pos)
+  {
+    if (pos.y == 0 || pos.y == 4)
+      pos.x = std::clamp(pos.x, 2, 2);
+    if (pos.y == 1 || pos.y == 3)
+      pos.x = std::clamp(pos.x, 1, 3);
+    if (pos.y == 2)
+      pos.x = std::clamp(pos.x, 0, 4);
+  }
+
+  void ClampY(Index2D& pos)
+  {
+    if (pos.x == 0 || pos.x == 4)
+      pos.y = std::clamp(pos.y, 2, 2);
+    if (pos.x == 1 || pos.x == 3)
+      pos.y = std::clamp(pos.y, 1, 3);
+    if (pos.x == 2)
+      pos.y = std::clamp(pos.y, 0, 4);
+  }
+
+  OUTPUT1(input)
+  {
+    Index2D pos{1, 1};
+    std::string code = "";
+    for (const auto& instructions : input)
+    {
+      for (const auto& instruction : instructions)
+      {
+        switch (instruction)
+        {
+          case 'R':
+            pos.x++;
+            break;
+          case 'L':
+            pos.x--;
+            break;
+          case 'U':
+            pos.y--;
+            break;
+          case 'D':
+            pos.y++;
+            break;
+        }
+        pos.x = std::clamp(pos.x, 0, 2);
+        pos.y = std::clamp(pos.y, 0, 2);
+      }
+      code += IndexToChar1(pos);
+    }
+    return code;
+  }
+
+  OUTPUT2(input)
+  {
+    Index2D pos{0, 2};
+    std::string code = "";
+    for (const auto& instructions : input)
+    {
+      for (const auto& instruction : instructions)
+      {
+        switch (instruction)
+        {
+          case 'R':
+            pos.x++;
+            ClampX(pos);
+            break;
+          case 'L':
+            pos.x--;
+            ClampX(pos);
+            break;
+          case 'U':
+            pos.y--;
+            ClampY(pos);
+            break;
+          case 'D':
+            pos.y++;
+            ClampY(pos);
+            break;
+        }
+      }
+      code += IndexToChar2(pos);
+    }
+    return code;
+  }
+}

src/2016/Day03.cpp

@@ -0,0 +1,52 @@
+#include "common/aoc.h"
+
+namespace y2016::day03
+{
+  REGISTER_DAY(2016, Day03, Array2D<int>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day03, ExampleInput, 1, 2);
+  REGISTER_TEST(2016, Day03, Input, 1, 983);
+  REGISTER_TEST_EXAMPLE(2016, Day03, ExampleInput, 2, 2);
+  REGISTER_TEST(2016, Day03, Input, 2, 1836);
+
+  READ_INPUT(input)
+  {
+    return Input::ReadIntsAsArray2D(input);
+  }
+
+  bool IsValid(const std::array<int, 3>& triangle)
+  {
+    for (int i = 0; i < 3; i++)
+    {
+      int length = triangle.at(i) + triangle.at((i + 1) % 3);
+      if (length <= triangle.at((i + 2) % 3))
+        return false;
+    }
+    return true;
+  }
+
+  OUTPUT1(input)
+  {
+    int count = 0;
+    for (int y = 0; y < input.height; y++)
+    {
+      if (IsValid({input.Get(0, y), input.Get(1, y), input.Get(2, y)}))
+        count++;
+    }
+    return count;
+  }
+
+  OUTPUT2(input)
+  {
+    int count = 0;
+    for (int y = 0; y < input.height; y += 3)
+    {
+      for (int x = 0; x < 3; x++)
+      {
+        if (IsValid({input.Get(x, y), input.Get(x, y + 1), input.Get(x, y + 2)}))
+          count++;
+      }
+    }
+    return count;
+  }
+}

src/2016/Day04.cpp

@@ -0,0 +1,109 @@
+#include "common/aoc.h"
+
+namespace y2016::day04
+{
+  struct Room
+  {
+    std::string name;
+    int sectorId;
+    std::string checksum;
+  };
+
+  REGISTER_DAY(2016, Day04, std::vector<Room>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day04, ExampleInput, 1, 1514);
+  REGISTER_TEST(2016, Day04, Input, 1, 278221);
+  REGISTER_TEST(2016, Day04, Input, 2, 267);
+
+  READ_INPUT(input)
+  {
+    std::vector<Room> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+      Room room;
+      std::stringstream ss{str};
+
+      getline(ss, room.name, '[');
+      size_t pos = room.name.find_last_of('-');
+      room.sectorId = std::strtoll(room.name.c_str() + pos + 1, nullptr, 10);
+      room.name = room.name.substr(0, pos);
+
+      getline(ss, room.checksum, ']');
+      vec.emplace_back(room);
+    }
+    return vec;
+  }
+
+  struct CharCount
+  {
+    char c;
+    int count;
+
+    bool operator<(const CharCount& rhs) const
+    {
+      if (count != rhs.count)
+        return count > rhs.count;
+      return c < rhs.c;
+    }
+  };
+
+  bool ValidRoom(const Room& room)
+  {
+    std::array<int, 'z' - 'a' + 1> counts;
+    counts.fill(0);
+    for (auto c : room.name)
+    {
+      if (c >= 'a' && c <= 'z')
+        counts[c - 'a']++;
+    }
+
+    std::set<CharCount> mostUsed;
+    for (int i = 0; i < counts.size(); i++)
+    {
+      if (counts[i] > 0)
+        mostUsed.emplace(CharCount{(char)('a' + i), counts[i]});
+    }
+
+    int i = 0;
+    for (auto it = mostUsed.begin(); i < 5; it++, i++)
+    {
+      if (room.checksum[i] != it->c)
+      {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  OUTPUT1(input)
+  {
+    int count = 0;
+    for (const auto& room : input)
+    {
+      if (ValidRoom(room))
+        count += room.sectorId;
+    }
+    return count;
+  }
+
+  OUTPUT2(input)
+  {
+    for (const auto& room : input)
+    {
+      if (!ValidRoom(room))
+        continue;
+
+      std::string newName = room.name;
+      for (auto& c : newName)
+      {
+        if (c >= 'a' && c <= 'z')
+          c = ((c - 'a') + room.sectorId) % ('z' - 'a' + 1) + 'a';
+      }
+
+      if (newName == "northpole-object-storage")
+        return room.sectorId;
+    }
+    return 0;
+  }
+}

src/2016/Day05.cpp

@@ -0,0 +1,61 @@
+#include "common/aoc.h"
+
+namespace y2016::day05
+{
+  REGISTER_DAY(2016, Day05, std::string, std::string);
+
+  REGISTER_TEST(2016, Day05, Input, 1, "f97c354d");
+  REGISTER_TEST(2016, Day05, Input, 2, "863dde27");
+
+  READ_INPUT(input)
+  {
+    std::string str;
+    getline(input, str);
+    return str;
+  }
+
+  OUTPUT1(input)
+  {
+    int i = 0;
+    std::string result;
+    while (true)
+    {
+      std::string str = input + std::to_string(i);
+      std::string s = Md5::Hash(str);
+      if (Helper::StartsWith(s, "00000"))
+      {
+        result.push_back(s[5]);
+        if (result.size() == 8)
+          return result;
+      }
+      i++;
+    }
+    return "";
+  }
+
+  OUTPUT2(input)
+  {
+    int i = 0;
+    std::string result{"XXXXXXXX"};
+    int replacements = 0;
+    for (int i = 0;; i++)
+    {
+      std::string str = input + std::to_string(i);
+      std::string s = Md5::Hash(str);
+      if (Helper::StartsWith(s, "00000"))
+      {
+        if (s[5] < '0' || s[5] > '7')
+          continue;
+
+        if (result[s[5] - '0'] == 'X')
+        {
+          result[s[5] - '0'] = s[6];
+          replacements++;
+        }
+        if (replacements == 8)
+          return result;
+      }
+    }
+    return "";
+  }
+}

src/2016/Day06.cpp

@@ -0,0 +1,66 @@
+#include "common/aoc.h"
+
+namespace y2016::day06
+{
+  REGISTER_DAY(2016, Day06, Array2D<char>, std::string);
+
+  REGISTER_TEST_EXAMPLE(2016, Day06, ExampleInput, 1, "easter");
+  REGISTER_TEST(2016, Day06, Input, 1, "xhnqpqql");
+  REGISTER_TEST_EXAMPLE(2016, Day06, ExampleInput, 2, "advent");
+  REGISTER_TEST(2016, Day06, Input, 2, "brhailro");
+
+  READ_INPUT(input)
+  {
+    return Input::ReadArray2D(input);
+  }
+
+  OUTPUT1(input)
+  {
+    std::string result;
+    for (int x = 0; x < input.width; x++)
+    {
+      std::map<char, int> map;
+      for (int y = 0; y < input.height; y++)
+      {
+        map[input.Get(x, y)]++;
+      }
+      int max = 0;
+      char maxChar;
+      for (const auto& [c, count] : map)
+      {
+        if (count > max)
+        {
+          maxChar = c;
+          max = count;
+        }
+      }
+      result.push_back(maxChar);
+    }
+    return result;
+  }
+
+  OUTPUT2(input)
+  {
+    std::string result;
+    for (int x = 0; x < input.width; x++)
+    {
+      std::map<char, int> map;
+      for (int y = 0; y < input.height; y++)
+      {
+        map[input.Get(x, y)]++;
+      }
+      int min = std::numeric_limits<int>::max();
+      char minChar;
+      for (const auto& [c, count] : map)
+      {
+        if (count < min)
+        {
+          minChar = c;
+          min = count;
+        }
+      }
+      result.push_back(minChar);
+    }
+    return result;
+  }
+}

src/2016/Day07.cpp

@@ -0,0 +1,166 @@
+#include "common/aoc.h"
+
+namespace y2016::day07
+{
+  struct IP
+  {
+    std::vector<std::string> s;
+    std::vector<std::string> hypernets;
+
+    friend std::ostream& operator<<(std::ostream& os, const IP& ip)
+    {
+      for (int i = 0; i < ip.s.size() + ip.hypernets.size(); i++)
+      {
+        if (i % 2 == 0)
+          os << ip.s[i / 2] << " ";
+        else
+          os << "[" << ip.hypernets[i / 2] << "] ";
+      }
+      return os;
+    }
+  };
+
+  REGISTER_DAY(2016, Day07, std::vector<IP>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day07, ExampleInput, 1, 2);
+  REGISTER_TEST(2016, Day07, Input, 1, 115);
+  REGISTER_TEST_EXAMPLE(2016, Day07, ExampleInput, 2, 3);
+  REGISTER_TEST(2016, Day07, Input, 2, 231);
+
+  READ_INPUT(input)
+  {
+    std::vector<IP> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+      IP ip;
+      bool readHypernet = false;
+      char c = '[';
+      size_t prevPos = 0;
+      size_t pos = str.find(c);
+      while (pos != std::string::npos)
+      {
+        if (!readHypernet)
+        {
+          c = ']';
+          ip.s.emplace_back(str.substr(prevPos, pos - prevPos));
+        }
+        else
+        {
+          c = '[';
+          ip.hypernets.emplace_back(str.substr(prevPos, pos - prevPos));
+        }
+        prevPos = pos + 1;
+        pos = str.find(c, prevPos);
+        readHypernet = !readHypernet;
+      }
+      ip.s.emplace_back(str.substr(prevPos));
+      vec.emplace_back(ip);
+    }
+    return vec;
+  }
+
+  bool HasABBA(const std::string& str)
+  {
+    for (size_t i = 0; i < str.size() - 3; i++)
+    {
+      if (str[i] == str[i + 3] && str[i + 1] == str[i + 2] && str[i] != str[i + 1])
+        return true;
+    }
+
+    return false;
+  }
+
+  bool SupportsTLS(const IP& ip)
+  {
+    for (const auto& hypernet : ip.hypernets)
+    {
+      if (HasABBA(hypernet))
+      {
+        return false;
+      }
+    }
+
+    for (const auto& s : ip.s)
+    {
+      if (HasABBA(s))
+      {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  std::vector<std::pair<char, char>> GetABAs(const std::string& str)
+  {
+    std::vector<std::pair<char, char>> result;
+    for (size_t i = 0; i < str.size() - 2; i++)
+    {
+      if (str[i] == str[i + 2] && str[i] != str[i + 1])
+        result.emplace_back(str[i], str[i + 1]);
+    }
+    return result;
+  }
+
+  bool HasABA(const std::string& str, char c1, char c2)
+  {
+    for (size_t i = 0; i < str.size() - 2; i++)
+    {
+      if (str[i] == c1 && str[i + 1] == c2 && str[i + 2] == c1)
+        return true;
+    }
+    return false;
+  }
+
+  bool HasABA(const std::vector<std::string>& hypernets, char c1, char c2)
+  {
+    for (const auto& hypernet : hypernets)
+    {
+      if (HasABA(hypernet, c1, c2))
+        return true;
+    }
+    return false;
+  }
+
+  bool SupportsSSL(const IP& ip)
+  {
+    for (const auto& s : ip.s)
+    {
+      std::vector<std::pair<char, char>> abas = GetABAs(s);
+      for (const auto& aba : abas)
+      {
+        if (HasABA(ip.hypernets, aba.second, aba.first))
+        {
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
+  OUTPUT1(input)
+  {
+    int count = 0;
+    for (const auto& ip : input)
+    {
+      if (SupportsTLS(ip))
+      {
+        count++;
+      }
+    }
+    return count;
+  }
+
+  OUTPUT2(input)
+  {
+    int count = 0;
+    for (const auto& ip : input)
+    {
+      if (SupportsSSL(ip))
+      {
+        count++;
+      }
+    }
+    return count;
+  }
+}

src/2016/Day08.cpp

@@ -0,0 +1,101 @@
+#include "common/aoc.h"
+
+namespace y2016::day08
+{
+  enum class Operation
+  {
+    Rect,
+    Col,
+    Row
+  };
+
+  struct Instruction
+  {
+    Operation operation;
+    int i1;
+    int i2;
+  };
+
+  REGISTER_DAY(2016, Day08, std::vector<Instruction>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day08, ExampleInput, 1, 6);
+  REGISTER_TEST(2016, Day08, Input, 1, 115);
+
+  READ_INPUT(input)
+  {
+    std::vector<Instruction> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+      Instruction instruction;
+      std::stringstream ss{str};
+      if (str[1] == 'e')  // rect
+      {
+        instruction.operation = Operation::Rect;
+        ss >> "rect " >> instruction.i1 >> "x" >> instruction.i2;
+      }
+      else if (str[7] == 'r')  // rotate row
+      {
+        instruction.operation = Operation::Row;
+        ss >> "rotate row y=" >> instruction.i1 >> "by " >> instruction.i2;
+      }
+      else  // rotate column
+      {
+        instruction.operation = Operation::Col;
+        ss >> "rotate column x=" >> instruction.i1 >> "by " >> instruction.i2;
+      }
+      vec.emplace_back(instruction);
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    Array2D<char> data{isExample ? 7 : 50, isExample ? 3 : 6, ' '};
+    for (const auto& instruction : input)
+    {
+      switch (instruction.operation)
+      {
+        case Operation::Rect:
+          for (int y = 0; y < instruction.i2; y++)
+          {
+            for (int x = 0; x < instruction.i1; x++)
+            {
+              data.Set(x, y, '#');
+            }
+          }
+          break;
+        case Operation::Row:
+          for (int i = 0; i < instruction.i2; i++)
+          {
+            char tmp = data.Get(data.width - 1, instruction.i1);
+            for (int x = data.width - 1; x > 0; x--)
+            {
+              data.Set(x, instruction.i1, data.Get(x - 1, instruction.i1));
+            }
+            data.Set(0, instruction.i1, tmp);
+          }
+          break;
+        case Operation::Col:
+          for (int i = 0; i < instruction.i2; i++)
+          {
+            char tmp = data.Get(instruction.i1, data.height - 1);
+            for (int y = data.height - 1; y > 0; y--)
+            {
+              data.Set(instruction.i1, y, data.Get(instruction.i1, y - 1));
+            }
+            data.Set(instruction.i1, 0, tmp);
+          }
+          break;
+      }
+    }
+    std::cout << data << std::endl;
+    return data.Count('#');
+  }
+
+  OUTPUT2(input)
+  {
+    // Solution is printed in Part 1
+    return 0;
+  }
+}

src/2016/Day09.cpp

@@ -0,0 +1,75 @@
+#include "common/aoc.h"
+
+namespace y2016::day09
+{
+  REGISTER_DAY(2016, Day09, std::string, uint64_t);
+
+  REGISTER_TEST_EXAMPLE(2016, Day09, ExampleInput, 1, 18);
+  REGISTER_TEST(2016, Day09, Input, 1, 99145);
+  REGISTER_TEST_EXAMPLE(2016, Day09, ExampleInput, 2, 20);
+  REGISTER_TEST(2016, Day09, Input, 2, 10943094568);
+
+  READ_INPUT(input)
+  {
+    std::string str;
+    getline(input, str);
+    return str;
+  }
+
+  std::pair<int, int> GetMarker(const char* str)
+  {
+    char* end;
+    int length = std::strtol(str, &end, 10);
+    int repeat = std::strtol(end + 1, nullptr, 10);
+    return {length, repeat};
+  }
+
+  uint64_t GetLength(const char* str, size_t strLength)
+  {
+    size_t i = 0;
+    uint64_t count = 0;
+    while (i < strLength)
+    {
+      if (str[i] == '(')
+      {
+        size_t close = std::strstr(str + i, ")") - str;
+        auto [length, repeat] = GetMarker(str + i + 1);
+        count += GetLength(str + close + 1, length) * repeat;
+        i = close + 1 + length;
+      }
+      else
+      {
+        count++;
+        i++;
+      }
+    }
+    return count;
+  }
+
+  OUTPUT1(input)
+  {
+    uint64_t count = 0;
+    size_t i = 0;
+    while (i < input.size())
+    {
+      if (input[i] == '(')
+      {
+        size_t close = input.find(')', i);
+        auto [length, repeat] = GetMarker(input.c_str() + i + 1);
+        count += length * repeat;
+        i = close + 1 + length;
+      }
+      else
+      {
+        count++;
+        i++;
+      }
+    }
+    return count;
+  }
+
+  OUTPUT2(input)
+  {
+    return GetLength(input.c_str(), input.size());
+  }
+}

src/2016/Day10.cpp

@@ -0,0 +1,146 @@
+#include "common/aoc.h"
+
+namespace y2016::day10
+{
+  enum class Output
+  {
+    Output,
+    Bot
+  };
+
+  struct Bot
+  {
+    std::vector<int> inputs;
+    int lowId{-1};
+    int highId{-1};
+    Output lowOutput;
+    Output highOutput;
+  };
+
+  using Bots = std::map<int, Bot>;
+  REGISTER_DAY(2016, Day10, Bots, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day10, ExampleInput, 1, 2);
+  REGISTER_TEST(2016, Day10, Input, 1, 47);
+  REGISTER_TEST_EXAMPLE(2016, Day10, ExampleInput, 2, 30);
+  REGISTER_TEST(2016, Day10, Input, 2, 2666);
+
+  READ_INPUT(input)
+  {
+    std::map<int, Bot> map;
+    std::string str;
+    while (getline(input, str))
+    {
+      std::stringstream ss{str};
+      if (str[0] == 'v')
+      {
+        int value;
+        int id;
+        ss >> "value" >> value >> "goes to bot " >> id;
+        map[id].inputs.emplace_back(value);
+      }
+      else
+      {
+        int idFrom;
+        int idLow;
+        int idHigh;
+        std::string typeLow;
+        std::string typeHigh;
+        ss >> "bot " >> idFrom >> "gives low to " >> typeLow >> idLow >> "and high to " >> typeHigh >> idHigh;
+        Bot& from = map[idFrom];
+        from.lowId = idLow;
+        from.highId = idHigh;
+        if (typeLow == "bot")
+          from.lowOutput = Output::Bot;
+        else
+          from.lowOutput = Output::Output;
+        if (typeHigh == "bot")
+          from.highOutput = Output::Bot;
+        else
+          from.highOutput = Output::Output;
+      }
+    }
+    return map;
+  }
+
+  bool HasInput(const Bot& bot, int input1, int input2)
+  {
+    return bot.inputs.size() == 2 && ((bot.inputs[0] == input1 && bot.inputs[1] == input2) ||
+                                      (bot.inputs[0] == input2 && bot.inputs[1] == input1));
+  }
+
+  OUTPUT1(input)
+  {
+    int input1 = isExample ? 5 : 61;
+    int input2 = isExample ? 2 : 17;
+    std::map<int, Bot> bots = input;
+    while (true)
+    {
+      for (auto it = bots.begin(); it != bots.end();)
+      {
+        if (HasInput(it->second, input1, input2))
+          return it->first;
+
+        if (it->second.inputs.size() == 2)
+        {
+          int low = Helper::Min(it->second.inputs);
+          int high = Helper::Max(it->second.inputs);
+          if (it->second.lowOutput == Output::Bot)
+          {
+            bots[it->second.lowId].inputs.emplace_back(low);
+            if (HasInput(bots[it->second.lowId], input1, input2))
+              return it->second.lowId;
+          }
+
+          if (it->second.highOutput == Output::Bot)
+          {
+            bots[it->second.highId].inputs.emplace_back(high);
+            if (HasInput(bots[it->second.highId], input1, input2))
+              return it->second.highId;
+          }
+          it = bots.erase(it);
+        }
+        else
+        {
+          it++;
+        }
+      }
+    }
+    return -1;
+  }
+
+  OUTPUT2(input)
+  {
+    std::map<int, int> outputs;
+    int input1 = isExample ? 5 : 61;
+    int input2 = isExample ? 2 : 17;
+    std::map<int, Bot> bots = input;
+    while (!bots.empty())
+    {
+      for (auto it = bots.begin(); it != bots.end();)
+      {
+        if (it->second.inputs.size() == 2)
+        {
+          int low = Helper::Min(it->second.inputs);
+          int high = Helper::Max(it->second.inputs);
+          if (it->second.lowOutput == Output::Bot)
+            bots[it->second.lowId].inputs.emplace_back(low);
+          else
+            outputs[it->second.lowId] = low;
+
+          if (it->second.highOutput == Output::Bot)
+            bots[it->second.highId].inputs.emplace_back(high);
+          else
+            outputs[it->second.highId] = high;
+
+          it = bots.erase(it);
+        }
+        else
+        {
+          it++;
+        }
+      }
+    }
+    return outputs[0] * outputs[1] * outputs[2];
+  }
+}

src/2016/Day11.cpp

@@ -0,0 +1,220 @@
+#include "common/aoc.h"
+
+namespace y2016::day11
+{
+  struct Item
+  {
+    int floorPos;
+    bool generator;
+    int id;
+
+    bool operator==(const Item& item) const
+    {
+      return floorPos == item.floorPos && id == item.id && generator == item.generator;
+    }
+  };
+
+  static int FLOORS = 4;
+
+  REGISTER_DAY(2016, Day11, std::vector<Item>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day11, ExampleInput, 1, 11);
+  REGISTER_TEST(2016, Day11, Input, 1, 37);
+  REGISTER_TEST(2016, Day11, Input, 2, 61);
+
+  Item ParseItem(const std::string_view& str, int floorPos, std::map<std::string, int>& nameToId)
+  {
+    size_t posDash = str.find('-');
+    std::string name;
+    bool generator;
+    if (posDash == std::string::npos)
+    {
+      name = str.substr(0, str.find(' '));
+      generator = true;
+    }
+    else
+    {
+      name = str.substr(0, posDash);
+      generator = false;
+    }
+    auto it = nameToId.find(name);
+    if (it != nameToId.end())
+      return Item{floorPos, generator, it->second};
+    int size = nameToId.size();
+    nameToId[name] = size;
+
+    return Item{floorPos, generator, size};
+  }
+
+  READ_INPUT(input)
+  {
+    std::vector<Item> vec;
+    std::string str;
+    std::map<std::string, int> nameToId;
+    for (int i = 0; i < FLOORS; i++)
+    {
+      getline(input, str);
+      std::vector<std::string_view> split = Helper::Split(str, " a ");
+      for (size_t j = 1; j < split.size(); j++)
+      {
+        vec.emplace_back(ParseItem(split[j], i, nameToId));
+      }
+    }
+    return vec;
+  }
+
+  struct State
+  {
+    std::vector<Item> items;
+    int elevatorPos;
+
+    int amountOfPairs;
+
+    std::vector<std::pair<int, int>> GetPairs() const
+    {
+      // Convert the data to a format where the pairs of generator/microchip don't matter. All that matters are their
+      // positions
+      std::vector<std::pair<int, int>> pairs(amountOfPairs);
+      for (const auto& item : items)
+      {
+        if (item.generator)
+          pairs[item.id].first = item.floorPos;
+        else
+          pairs[item.id].second = item.floorPos;
+      }
+      std::sort(pairs.begin(), pairs.end());
+      return pairs;
+    }
+
+    bool operator<(const State& state) const
+    {
+      if (elevatorPos != state.elevatorPos)
+        return elevatorPos < state.elevatorPos;
+      return GetPairs() < state.GetPairs();
+    }
+  };
+
+  bool HasItem(const State& state, int floor, bool generator, int id)
+  {
+    return std::find(state.items.begin(), state.items.end(), Item{floor, generator, id}) != state.items.end();
+  }
+
+  bool IsValidState(const State& state)
+  {
+    for (int i = 0; i < FLOORS; i++)
+    {
+      bool hasChipNotConnected = false;
+      int generators = 0;
+      for (const auto& item : state.items)
+      {
+        if (item.floorPos != i)
+          continue;
+        if (item.generator)
+        {
+          generators++;
+          continue;
+        }
+
+        if (HasItem(state, i, true, item.id))
+          continue;
+        hasChipNotConnected = true;
+      }
+      if (hasChipNotConnected && generators > 0)
+      {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  std::vector<std::pair<int, State>> Branch(const std::vector<Item>& input, const State& state)
+  {
+    std::vector<std::pair<int, State>> branches;
+    for (int i = -1; i <= 1; i += 2)
+    {
+      if (state.elevatorPos + i < 0 || state.elevatorPos + i > 3)
+        continue;
+
+      State newState = state;
+      newState.elevatorPos += i;
+      for (auto& item : newState.items)
+      {
+        if (item.floorPos != state.elevatorPos)
+          continue;
+
+        item.floorPos = newState.elevatorPos;
+        if (IsValidState(newState))
+          branches.emplace_back(1, newState);
+        item.floorPos = state.elevatorPos;
+      }
+
+      for (size_t i = 0; i < newState.items.size(); i++)
+      {
+        if (newState.items[i].floorPos != state.elevatorPos)
+          continue;
+        newState.items[i].floorPos = newState.elevatorPos;
+
+        for (size_t j = i + 1; j < newState.items.size(); j++)
+        {
+          if (newState.items[j].floorPos != state.elevatorPos)
+            continue;
+          newState.items[j].floorPos = newState.elevatorPos;
+          if (IsValidState(newState))
+            branches.emplace_back(1, newState);
+          newState.items[j].floorPos = state.elevatorPos;
+        }
+        newState.items[i].floorPos = state.elevatorPos;
+      }
+    }
+    return branches;
+  }
+
+  bool Goal(const std::vector<Item>& input, const State& state)
+  {
+    for (size_t i = 0; i < state.items.size(); i++)
+    {
+      if (state.items[i].floorPos != 3)
+        return false;
+    }
+    return true;
+  }
+
+  int Heuristic(const std::vector<Item>& input, const State& state)
+  {
+    int heuristic = 0;
+    int moves = 0;
+    for (size_t i = 0; i < state.items.size(); i++)
+    {
+      moves += (3 - state.items[i].floorPos);
+    }
+    heuristic += moves / 2;
+    return heuristic;
+  }
+
+  OUTPUT1(input)
+  {
+    int max = 0;
+    for (const auto& item : input)
+    {
+      max = std::max(max, item.id);
+    }
+    State state{input, 0, max + 1};
+    return Helper::AStar(input, state, Heuristic, Branch, Goal);
+  }
+
+  OUTPUT2(input)
+  {
+    std::vector<Item> items = input;
+    int max = 0;
+    for (const auto& item : items)
+    {
+      max = std::max(max, item.id);
+    }
+    items.emplace_back(Item{0, true, max + 1});
+    items.emplace_back(Item{0, false, max + 1});
+    items.emplace_back(Item{0, true, max + 2});
+    items.emplace_back(Item{0, false, max + 2});
+    State state{items, 0, max + 3};
+    return Helper::AStar(input, state, Heuristic, Branch, Goal);
+  }
+}

src/2016/Day12.cpp

@@ -0,0 +1,116 @@
+#include "common/aoc.h"
+
+namespace y2016::day12
+{
+  enum class Operator
+  {
+    Cpy,
+    Inc,
+    Dec,
+    Jnz
+  };
+
+  struct Instruction
+  {
+    Operator op;
+    std::variant<char, int> arg1;
+    std::variant<char, int> arg2;
+  };
+
+  REGISTER_DAY(2016, Day12, std::vector<Instruction>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day12, ExampleInput, 1, 42);
+  REGISTER_TEST(2016, Day12, Input, 1, 318007);
+  REGISTER_TEST_EXAMPLE(2016, Day12, ExampleInput, 2, 42);
+  REGISTER_TEST(2016, Day12, Input, 2, 9227661);
+
+  READ_INPUT(input)
+  {
+    std::vector<Instruction> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+      Instruction instruction;
+      if (str[0] == 'c')
+      {
+        instruction.op = Operator::Cpy;
+        if (str[4] >= 'a' && str[4] <= 'd')
+          instruction.arg1 = str[4];
+        else
+          instruction.arg1 = (int)std::atoi(str.c_str() + 4);
+        instruction.arg2 = str[str.size() - 1];
+      }
+      else if (str[0] == 'i')
+      {
+        instruction.op = Operator::Inc;
+        instruction.arg1 = str[4];
+      }
+      else if (str[0] == 'd')
+      {
+        instruction.op = Operator::Dec;
+        instruction.arg1 = str[4];
+      }
+      else if (str[0] == 'j')
+      {
+        instruction.op = Operator::Jnz;
+        if (str[4] >= 'a' && str[4] <= 'd')
+          instruction.arg1 = str[4];
+        else
+          instruction.arg1 = (int)std::atoi(str.c_str() + 4);
+        instruction.arg2 = atoi(str.c_str() + 6);
+      }
+      vec.emplace_back(instruction);
+    }
+    return vec;
+  }
+
+  int Run(const std::vector<Instruction>& instructions, std::vector<int> registers)
+  {
+    size_t pc = 0;
+    while (pc < instructions.size())
+    {
+      switch (instructions[pc].op)
+      {
+        case Operator::Cpy:
+        {
+          int number = 0;
+          if (std::holds_alternative<int>(instructions[pc].arg1))
+            number = std::get<int>(instructions[pc].arg1);
+          else
+            number = registers[std::get<char>(instructions[pc].arg1) - 'a'];
+          registers[std::get<char>(instructions[pc].arg2) - 'a'] = number;
+          break;
+        }
+        case Operator::Inc:
+          registers[std::get<char>(instructions[pc].arg1) - 'a']++;
+          break;
+        case Operator::Dec:
+          registers[std::get<char>(instructions[pc].arg1) - 'a']--;
+          break;
+        case Operator::Jnz:
+          int value = 0;
+          if (std::holds_alternative<int>(instructions[pc].arg1))
+            value = std::get<int>(instructions[pc].arg1);
+          else
+            value = registers[std::get<char>(instructions[pc].arg1) - 'a'];
+          if (value != 0)
+            pc += std::get<int>(instructions[pc].arg2) - 1;
+          break;
+      }
+      pc++;
+    }
+    return registers[0];
+  }
+
+  OUTPUT1(input)
+  {
+    return Run(input, std::vector<int>(4));
+  }
+
+  OUTPUT2(input)
+  {
+    std::vector<int> registers(4);
+    registers[2] = 1;
+    return Run(input, registers);
+  }
+}

src/2016/Day13.cpp

@@ -0,0 +1,103 @@
+#include "common/aoc.h"
+
+namespace y2016::day13
+{
+  REGISTER_DAY(2016, Day13, int, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day13, ExampleInput, 1, 11);
+  REGISTER_TEST(2016, Day13, Input, 1, 82);
+  REGISTER_TEST_EXAMPLE(2016, Day13, ExampleInput, 2, 151);
+  REGISTER_TEST(2016, Day13, Input, 2, 138);
+
+  READ_INPUT(input)
+  {
+    int i;
+    input >> i;
+    return i;
+  }
+
+  bool IsWall(int x, int y, int number)
+  {
+    int i = x * x + 3 * x + 2 * x * y + y + y * y;
+    i += number;
+    std::string str = std::bitset<32>(i).to_string();
+    // std::cout << str << ": " << std::count(str.begin(), str.end(), '1') % 2 << std::endl;
+    return std::count(str.begin(), str.end(), '1') % 2 != 0;
+  }
+
+  struct State
+  {
+    int x;
+    int y;
+
+    bool operator==(const State& state) const
+    {
+      return x == state.x && y == state.y;
+    }
+
+    bool operator<(const State& state) const
+    {
+      if (x != state.x)
+        return x < state.x;
+      return y < state.y;
+    }
+
+    friend std::ostream& operator<<(std::ostream& os, const State& state)
+    {
+      return os << "(" << state.x << ", " << state.y << ")";
+    }
+  };
+
+  std::vector<std::pair<int, State>> Branch(int input, const State& state)
+  {
+    std::vector<std::pair<int, State>> branches;
+    if (state.x > 0 && !IsWall(state.x - 1, state.y, input))
+      branches.emplace_back(1, State{state.x - 1, state.y});
+    if (state.y > 0 && !IsWall(state.x, state.y - 1, input))
+      branches.emplace_back(1, State{state.x, state.y - 1});
+    if (!IsWall(state.x + 1, state.y, input))
+      branches.emplace_back(1, State{state.x + 1, state.y});
+    if (!IsWall(state.x, state.y + 1, input))
+      branches.emplace_back(1, State{state.x, state.y + 1});
+    return branches;
+  }
+
+  bool Goal(int input, const State& state)
+  {
+    if (input == 10)
+      return state == State{7, 4};
+    else
+      return state == State{31, 39};
+  }
+
+  OUTPUT1(input)
+  {
+    State state{1, 1};
+    return Helper::Dijkstras(input, state, Branch, Goal);
+  }
+
+  OUTPUT2(input)
+  {
+    std::queue<std::pair<int, State>> queue{};
+    queue.emplace(0, State{1, 1});
+    std::set<State> visited;
+    while (!queue.empty())
+    {
+      std::pair<int, State> state = queue.front();
+      queue.pop();
+
+      std::vector<std::pair<int, State>> branches = Branch(input, state.second);
+      for (const auto& branch : branches)
+      {
+        if (!visited.emplace(branch.second).second)
+          continue;
+
+        if (state.first >= 49)
+          continue;
+        else
+          queue.emplace(state.first + 1, branch.second);
+      }
+    }
+    return visited.size();
+  }
+}

src/2016/Day14.cpp

@@ -0,0 +1,113 @@
+#include "common/aoc.h"
+
+namespace y2016::day14
+{
+  REGISTER_DAY(2016, Day14, std::string, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day14, ExampleInput, 1, 22728);
+  REGISTER_TEST(2016, Day14, Input, 1, 15035);
+  REGISTER_TEST_EXAMPLE(2016, Day14, ExampleInput, 2, 22551);
+  REGISTER_TEST(2016, Day14, Input, 2, 19968);
+
+  READ_INPUT(input)
+  {
+    std::string str;
+    getline(input, str);
+    return str;
+  }
+
+  char GetConsecutive(const std::string& s, int count)
+  {
+    for (size_t i = 0; i < s.size(); i++)
+    {
+      bool found = true;
+      char c = s[i];
+      for (int j = 1; j < count; j++)
+      {
+        if (s[i + j] != c)
+        {
+          found = false;
+          break;
+        }
+      }
+      if (found)
+        return c;
+    }
+    return '\0';
+  }
+
+  std::set<char> GetConsecutives(const std::string& s, int count)
+  {
+    std::set<char> consecutives;
+    for (size_t i = 0; i < s.size(); i++)
+    {
+      char c = s[i];
+      bool found = true;
+      for (int j = 0; j < count; j++)
+      {
+        if (s[i + j] != c)
+        {
+          found = false;
+          break;
+        }
+      }
+      if (found)
+        consecutives.emplace(c);
+    }
+    return consecutives;
+  }
+
+  void Hash(std::string& s, int count)
+  {
+    for (int i = 0; i < count; i++)
+      s = Md5::Hash(s);
+  }
+
+  int FindKeys(const std::string& str, int repeat)
+  {
+    std::vector<int> foundKeys;
+    std::map<int, char> keys;
+    int i = 0;
+    int upperLimit = std::numeric_limits<int>::max();
+    while (i < upperLimit)
+    {
+      keys.erase(i - 1000);
+
+      std::string hash = str + std::to_string(i);
+      Hash(hash, repeat + 1);
+      char c = GetConsecutive(hash, 3);
+      std::set<char> consecutives = GetConsecutives(hash, 5);
+
+      for (auto it = keys.begin(); it != keys.end();)
+      {
+        if (consecutives.count(it->second) != 0)
+        {
+          foundKeys.emplace_back(it->first);
+          if (foundKeys.size() == 64)
+            upperLimit = it->first + 1000;
+          it = keys.erase(it);
+        }
+        else
+        {
+          it++;
+        }
+      }
+
+      if (c != '\0')
+        keys.emplace(i, c);
+      i++;
+    }
+    std::sort(foundKeys.begin(), foundKeys.end());
+    return foundKeys[63];
+  }
+
+  OUTPUT1(input)
+  {
+    return FindKeys(input, 0);
+  }
+
+  OUTPUT2(input)
+  {
+    return FindKeys(input, 2016);
+  }
+}

src/2016/Day15.cpp

@@ -0,0 +1,58 @@
+#include "common/aoc.h"
+
+namespace y2016::day15
+{
+  struct Disc
+  {
+    int positions;
+    int position;
+  };
+
+  REGISTER_DAY(2016, Day15, std::vector<Disc>, int64_t);
+
+  REGISTER_TEST_EXAMPLE(2016, Day15, ExampleInput, 1, 25);
+  REGISTER_TEST(2016, Day15, Input, 1, 400589);
+  REGISTER_TEST_EXAMPLE(2016, Day15, ExampleInput, 2, 205);
+  REGISTER_TEST(2016, Day15, Input, 2, 3045959);
+
+  READ_INPUT(input)
+  {
+    std::vector<Disc> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+      std::stringstream ss{str};
+      int i;
+      Disc disc;
+      ss >> "Disc #" >> i >> "has " >> disc.positions >> "positions; at time=" >> i >> ", it is at position " >>
+        disc.position;
+      vec.emplace_back(disc);
+    }
+    return vec;
+  }
+
+  int64_t Solve(const std::vector<Disc>& discs)
+  {
+    std::vector<int64_t> starts;
+    std::vector<int64_t> mods;
+    std::vector<int64_t> remainders(discs.size(), 0);
+    for (int j = 0; j < discs.size(); j++)
+    {
+      starts.emplace_back(discs[j].position + j + 1);
+      mods.emplace_back(discs[j].positions);
+    }
+    return Helper::ChineseRemainderTheorem(mods, remainders, starts);
+  }
+
+  OUTPUT1(input)
+  {
+    return Solve(input);
+  }
+
+  OUTPUT2(input)
+  {
+    auto discs = input;
+    discs.emplace_back(Disc{11, 0});
+    return Solve(discs);
+  }
+}

src/2016/Day16.cpp

@@ -0,0 +1,58 @@
+#include "common/aoc.h"
+
+namespace y2016::day16
+{
+  REGISTER_DAY(2016, Day16, std::string, std::string);
+
+  REGISTER_TEST_EXAMPLE(2016, Day16, ExampleInput, 1, "01100");
+  REGISTER_TEST(2016, Day16, Input, 1, "10100011010101011");
+  REGISTER_TEST(2016, Day16, Input, 2, "01010001101011001");
+
+  READ_INPUT(input)
+  {
+    std::string str;
+    getline(input, str);
+    return str;
+  }
+
+  std::string ReverseFlip(const std::string& str)
+  {
+    std::string reverse;
+    for (int i = str.size() - 1; i >= 0; i--)
+    {
+      reverse.push_back(str[i] == '1' ? '0' : '1');
+    }
+    return reverse;
+  }
+
+  std::string Solve(std::string str, int length)
+  {
+    while (str.size() < length)
+    {
+      str = str + "0" + ReverseFlip(str);
+    }
+    str = str.substr(0, length);
+
+    std::string checksum;
+    while (str.size() % 2 == 0)
+    {
+      for (int i = 0; i < str.size(); i += 2)
+      {
+        checksum.push_back(str[i] == str[i + 1] ? '1' : '0');
+      }
+      str = checksum;
+      checksum.clear();
+    }
+    return str;
+  }
+
+  OUTPUT1(input)
+  {
+    return Solve(input, isExample ? 20 : 272);
+  }
+
+  OUTPUT2(input)
+  {
+    return Solve(input, 35651584);
+  }
+}

src/2016/Day17.cpp

@@ -0,0 +1,85 @@
+#include "common/aoc.h"
+
+namespace y2016::day17
+{
+  REGISTER_DAY(2016, Day17, std::string, std::string);
+
+  REGISTER_TEST_EXAMPLE(2016, Day17, ExampleInput, 1, "DRURDRUDDLLDLUURRDULRLDUUDDDRR");
+  REGISTER_TEST(2016, Day17, Input, 1, "DUDDRLRRRD");
+  REGISTER_TEST_EXAMPLE(2016, Day17, ExampleInput, 2, "830");
+  REGISTER_TEST(2016, Day17, Input, 2, "578");
+
+  READ_INPUT(input)
+  {
+    std::vector<int> vec;
+    std::string str;
+    getline(input, str);
+    return str;
+  }
+
+  struct State
+  {
+    std::string str{""};
+    int x{0};
+    int y{0};
+  };
+
+  bool IsOpen(char c)
+  {
+    return c >= 'b' && c <= 'f';
+  }
+
+  void Branch(const State& state, std::queue<State>& queue)
+  {
+    std::string hash = Md5::Hash(state.str);
+    if (state.y > 0 && IsOpen(hash[0]))
+      queue.emplace(State{state.str + "U", state.x, state.y - 1});
+    if (state.y < 3 && IsOpen(hash[1]))
+      queue.emplace(State{state.str + "D", state.x, state.y + 1});
+    if (state.x > 0 && IsOpen(hash[2]))
+      queue.emplace(State{state.str + "L", state.x - 1, state.y});
+    if (state.x < 3 && IsOpen(hash[3]))
+      queue.emplace(State{state.str + "R", state.x + 1, state.y});
+  }
+
+  bool IsGoal(const State& state)
+  {
+    return state.x == 3 && state.y == 3;
+  }
+
+  OUTPUT1(input)
+  {
+    std::queue<State> queue;
+    queue.emplace(State{input, 0, 0});
+    while (!queue.empty())
+    {
+      State state = queue.front();
+      queue.pop();
+      if (IsGoal(state))
+        return state.str.substr(input.size());
+      Branch(state, queue);
+    }
+
+    return "";
+  }
+
+  OUTPUT2(input)
+  {
+    std::queue<State> queue;
+    queue.emplace(State{input, 0, 0});
+    int longest = 0;
+    while (!queue.empty())
+    {
+      State state = queue.front();
+      queue.pop();
+      if (IsGoal(state))
+      {
+        longest = state.str.size() - input.size();
+        continue;
+      }
+      Branch(state, queue);
+    }
+
+    return std::to_string(longest);
+  }
+}

src/2016/Day18.cpp

@@ -0,0 +1,57 @@
+#include "common/aoc.h"
+
+namespace y2016::day18
+{
+  REGISTER_DAY(2016, Day18, std::string, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day18, ExampleInput, 1, 38);
+  REGISTER_TEST(2016, Day18, Input, 1, 1913);
+  REGISTER_TEST_EXAMPLE(2016, Day18, ExampleInput, 2, 1935478);
+  REGISTER_TEST(2016, Day18, Input, 2, 19993564);
+
+  READ_INPUT(input)
+  {
+    std::string str;
+    getline(input, str);
+    return str;
+  }
+
+  int Solve(const std::string& str, int rows)
+  {
+    int safes = std::count(str.begin(), str.end(), '.');
+    std::vector<char> row(str.size() + 2, false);
+    for (int i = 0; i < str.size(); i++)
+      row[i + 1] = str[i] == '^';
+
+    for (int i = 1; i < rows; i++)
+    {
+      std::vector<char> newRow(row.size(), false);
+      for (int j = 1; j < newRow.size() - 1; j++)
+      {
+        bool isTrap = false;
+        if (row[j - 1] && row[j] && !row[j + 1])
+          newRow[j] = true;
+        else if (!row[j - 1] && row[j] && row[j + 1])
+          newRow[j] = true;
+        else if (row[j - 1] && !row[j] && !row[j + 1])
+          newRow[j] = true;
+        else if (!row[j - 1] && !row[j] && row[j + 1])
+          newRow[j] = true;
+        else
+          safes++;
+      }
+      row = newRow;
+    }
+    return safes;
+  }
+
+  OUTPUT1(input)
+  {
+    return Solve(input, isExample ? 10 : 40);
+  }
+
+  OUTPUT2(input)
+  {
+    return Solve(input, 400000);
+  }
+}

src/2016/Day19.cpp

@@ -0,0 +1,69 @@
+#include "common/aoc.h"
+
+namespace y2016::day19
+{
+  REGISTER_DAY(2016, Day19, int, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day19, ExampleInput, 1, 3);
+  REGISTER_TEST(2016, Day19, Input, 1, 1842613);
+  REGISTER_TEST_EXAMPLE(2016, Day19, ExampleInput, 2, 2);
+  REGISTER_TEST(2016, Day19, Input, 2, 1424135);
+
+  READ_INPUT(input)
+  {
+    int i;
+    input >> i;
+    return i;
+  }
+
+  OUTPUT1(input)
+  {
+    std::vector<int> elves(input, 0);
+    for (int i = 0; i < input; i++)
+    {
+      elves[i] = i + 1;
+    }
+    int offset = 0;
+    while (elves.size() > 1)
+    {
+      std::vector<int> newElves;
+      for (int i = offset; i < elves.size(); i += 2)
+      {
+        newElves.emplace_back(elves[i]);
+      }
+      offset = (offset + (elves.size() % 2)) % 2;
+      elves = newElves;
+    }
+    return elves[0];
+  }
+
+  OUTPUT2(input)
+  {
+    std::deque<int> start;
+    std::deque<int> end;
+    for (int i = 0; i < input / 2; i++)
+    {
+      start.push_back(i + 1);
+    }
+    for (int i = input / 2; i < input; i++)
+    {
+      end.push_back(i + 1);
+    }
+
+    while (!start.empty())
+    {
+      end.pop_front();
+
+      end.push_back(start.front());
+      start.pop_front();
+
+      if (end.size() - start.size() == 2)
+      {
+        start.push_back(end.front());
+        end.pop_front();
+      }
+    }
+
+    return end.front();
+  }
+}

src/2016/Day20.cpp

@@ -0,0 +1,31 @@
+#include "common/aoc.h"
+
+namespace y2016::day20
+{
+  REGISTER_DAY(2016, Day20, std::vector<int>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day20, ExampleInput, 1, 0);
+  REGISTER_TEST(2016, Day20, Input, 1, 0);
+  REGISTER_TEST_EXAMPLE(2016, Day20, ExampleInput, 2, 0);
+  REGISTER_TEST(2016, Day20, Input, 2, 0);
+
+  READ_INPUT(input)
+  {
+    std::vector<int> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    return 0;
+  }
+
+  OUTPUT2(input)
+  {
+    return 0;
+  }
+}

src/2016/Day21.cpp

@@ -0,0 +1,31 @@
+#include "common/aoc.h"
+
+namespace y2016::day21
+{
+  REGISTER_DAY(2016, Day21, std::vector<int>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day21, ExampleInput, 1, 0);
+  REGISTER_TEST(2016, Day21, Input, 1, 0);
+  REGISTER_TEST_EXAMPLE(2016, Day21, ExampleInput, 2, 0);
+  REGISTER_TEST(2016, Day21, Input, 2, 0);
+
+  READ_INPUT(input)
+  {
+    std::vector<int> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    return 0;
+  }
+
+  OUTPUT2(input)
+  {
+    return 0;
+  }
+}

src/2016/Day22.cpp

@@ -0,0 +1,31 @@
+#include "common/aoc.h"
+
+namespace y2016::day22
+{
+  REGISTER_DAY(2016, Day22, std::vector<int>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day22, ExampleInput, 1, 0);
+  REGISTER_TEST(2016, Day22, Input, 1, 0);
+  REGISTER_TEST_EXAMPLE(2016, Day22, ExampleInput, 2, 0);
+  REGISTER_TEST(2016, Day22, Input, 2, 0);
+
+  READ_INPUT(input)
+  {
+    std::vector<int> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    return 0;
+  }
+
+  OUTPUT2(input)
+  {
+    return 0;
+  }
+}

src/2016/Day23.cpp

@@ -0,0 +1,31 @@
+#include "common/aoc.h"
+
+namespace y2016::day23
+{
+  REGISTER_DAY(2016, Day23, std::vector<int>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day23, ExampleInput, 1, 0);
+  REGISTER_TEST(2016, Day23, Input, 1, 0);
+  REGISTER_TEST_EXAMPLE(2016, Day23, ExampleInput, 2, 0);
+  REGISTER_TEST(2016, Day23, Input, 2, 0);
+
+  READ_INPUT(input)
+  {
+    std::vector<int> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    return 0;
+  }
+
+  OUTPUT2(input)
+  {
+    return 0;
+  }
+}

src/2016/Day24.cpp

@@ -0,0 +1,31 @@
+#include "common/aoc.h"
+
+namespace y2016::day24
+{
+  REGISTER_DAY(2016, Day24, std::vector<int>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day24, ExampleInput, 1, 0);
+  REGISTER_TEST(2016, Day24, Input, 1, 0);
+  REGISTER_TEST_EXAMPLE(2016, Day24, ExampleInput, 2, 0);
+  REGISTER_TEST(2016, Day24, Input, 2, 0);
+
+  READ_INPUT(input)
+  {
+    std::vector<int> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    return 0;
+  }
+
+  OUTPUT2(input)
+  {
+    return 0;
+  }
+}

src/2016/Day25.cpp

@@ -0,0 +1,31 @@
+#include "common/aoc.h"
+
+namespace y2016::day25
+{
+  REGISTER_DAY(2016, Day25, std::vector<int>, int);
+
+  REGISTER_TEST_EXAMPLE(2016, Day25, ExampleInput, 1, 0);
+  REGISTER_TEST(2016, Day25, Input, 1, 0);
+  REGISTER_TEST_EXAMPLE(2016, Day25, ExampleInput, 2, 0);
+  REGISTER_TEST(2016, Day25, Input, 2, 0);
+
+  READ_INPUT(input)
+  {
+    std::vector<int> vec;
+    std::string str;
+    while (getline(input, str))
+    {
+    }
+    return vec;
+  }
+
+  OUTPUT1(input)
+  {
+    return 0;
+  }
+
+  OUTPUT2(input)
+  {
+    return 0;
+  }
+}

src/2021/Day08.cpp

@@ -28,7 +28,8 @@ namespace y2021::day08
         std::string s;
         ss >> s;
         std::set<char> set;
-        for (char c : s) set.emplace(c);
+        for (char c : s)
+          set.emplace(c);
         signal.numbers.emplace_back(set);
       }
       char c;
@@ -38,7 +39,8 @@ namespace y2021::day08
         std::string s;
         ss >> s;
         std::set<char> set;
-        for (char c : s) set.emplace(c);
+        for (char c : s)
+          set.emplace(c);
         signal.display.emplace_back(set);
       }
       signals.emplace_back(signal);

src/2021/Day11.cpp

@@ -5,7 +5,8 @@ namespace y2021::day11
 
   std::set<Index2D> CalculateFlashing(Array2D<int>& array)
   {
-    for (auto& val : array) val++;
+    for (auto& val : array)
+      val++;
     std::set<Index2D> flashed;
     bool hasChanged = true;
     while (hasChanged)
@@ -59,7 +60,8 @@ namespace y2021::day11
     {
       std::set<Index2D> flashed = CalculateFlashing(array);
       count += flashed.size();
-      for (auto& flash : flashed) array[flash] = 0;
+      for (auto& flash : flashed)
+        array[flash] = 0;
     }
     return count;
   }
@@ -74,7 +76,8 @@ namespace y2021::day11
       std::set<Index2D> flashed = CalculateFlashing(array);
       if (flashed.size() == array.width * array.height)
         return count;
-      for (auto& flash : flashed) array[flash] = 0;
+      for (auto& flash : flashed)
+        array[flash] = 0;
       count++;
     }
     return count;

src/2021/Day13.cpp

@@ -93,7 +93,7 @@ namespace y2021::day13
     {
       board[index] = '#';
     }
-    std::cout << board;
+    std::cout << board << std::endl;
     // Not the "correct" output to part 2, but it verifies something at least
     return indices.size();
   }

src/2021/Day18.cpp

@@ -272,7 +272,8 @@ namespace y2021::day18
     while (changed)
     {
       changed = false;
-      while (node.Explode()) changed = true;
+      while (node.Explode())
+        changed = true;
       if (node.Split())
         changed = true;
     }

src/2022/Day11.cpp

@@ -68,7 +68,8 @@ namespace y$1::day11
         std::getline(input, str);
         std::stringstream ss{str};
         ss >> "Starting items: ";
-        while (std::getline(ss, str, ',')) monkey.items.emplace_back(std::stoi(str));
+        while (std::getline(ss, str, ','))
+          monkey.items.emplace_back(std::stoi(str));
       }
       {  // operator
         std::getline(input, str);

src/2022/Day13.cpp

@@ -77,7 +77,8 @@ namespace y$1::day13
         Node node;
         node.nodes = std::stoi(str.substr(index));
         nodes.emplace_back(node);
-        while (str[index] >= '0' && str[index] <= '9') index++;
+        while (str[index] >= '0' && str[index] <= '9')
+          index++;
       }
       else
       {

src/2022/Day22.cpp

@@ -131,7 +131,8 @@ namespace y$1::day22
       if (input.directions[i] >= '0' && input.directions[i] <= '9')
       {
         int amount = std::stoi(&input.directions[i]);
-        while (input.directions[i] >= '0' && input.directions[i] <= '9') i++;
+        while (input.directions[i] >= '0' && input.directions[i] <= '9')
+          i++;
 
         for (int j = 0; j < amount; j++)
         {
@@ -219,7 +220,8 @@ namespace y$1::day22
       if (input.directions[i] >= '0' && input.directions[i] <= '9')
       {
         int amount = std::stoi(&input.directions[i]);
-        while (input.directions[i] >= '0' && input.directions[i] <= '9') i++;
+        while (input.directions[i] >= '0' && input.directions[i] <= '9')
+          i++;
 
         for (int j = 0; j < amount; j++)
         {

src/2022/Day25.cpp

@@ -39,7 +39,8 @@ namespace y$1::day25
     // Convert to base 5
     std::string base5 = "";
     int64_t numbers = log(base10) / log(5) + 1;
-    for (int i = 0; i < numbers + 1; i++) base5.push_back('0');
+    for (int i = 0; i < numbers + 1; i++)
+      base5.push_back('0');
     int64_t base5Max = Pow(5, numbers - 2);
 
     for (int i = 1; i < base5.size(); i++)

src/2023/Day03.cpp

@@ -55,7 +55,8 @@ namespace y2023::day03
         if (Helper::IsDigit(array.Get(x, y)))
         {
           Index2D numberStart = Index2D{x, y};
-          while (numberStart.x >= 0 && Helper::IsDigit(array.Get(numberStart))) numberStart.x--;
+          while (numberStart.x >= 0 && Helper::IsDigit(array.Get(numberStart)))
+            numberStart.x--;
           numberStart.x++;
 
           int number = GetNumber(array, numberStart);
@@ -64,7 +65,8 @@ namespace y2023::day03
           else
             return firstNum * number;
 
-          while (x < array.width && Helper::IsDigit(array.Get(x, y))) x++;
+          while (x < array.width && Helper::IsDigit(array.Get(x, y)))
+            x++;
           x--;
         }
       }
@@ -88,7 +90,8 @@ namespace y2023::day03
         if (Helper::IsDigit(input.Get(x, y)))
         {
           int i = 1;
-          while (x + i < input.width && Helper::IsDigit(input.Get(x + i, y))) i++;
+          while (x + i < input.width && Helper::IsDigit(input.Get(x + i, y)))
+            i++;
           if (HasAdjecent(input, Index2D{x, y}, i))
           {
             sum += GetNumber(input, Index2D{x, y});

src/2023/Day04.cpp

@@ -28,12 +28,14 @@ namespace y2023::day04
 
       std::stringstream ss{str};
       ss >> "Card " >> i >> ":";
-      while (ss >> i) game.winning.emplace_back(i);
+      while (ss >> i)
+        game.winning.emplace_back(i);
       ss.clear();  // clear the failbit to be able to read more data
 
       ss >> "|";
 
-      while (ss >> i) game.numbers.emplace(i);
+      while (ss >> i)
+        game.numbers.emplace(i);
 
       games.emplace_back(game);
     }

src/2023/Day05.cpp

@@ -82,7 +82,8 @@ namespace y2023::day05
     std::stringstream ss{str};
     int64_t i;
     ss >> "seeds: ";
-    while (ss >> i) plantation.seeds.emplace_back(i);
+    while (ss >> i)
+      plantation.seeds.emplace_back(i);
     std::getline(input, str);
     while (std::getline(input, str))
     {

src/2023/Day06.cpp

@@ -18,7 +18,8 @@ namespace y2023::day06
     std::stringstream ss{str};
     int i;
     ss >> "Time: ";
-    while (ss >> i) games.emplace_back(i, 0);
+    while (ss >> i)
+      games.emplace_back(i, 0);
 
     std::getline(input, str);
     std::stringstream ss2{str};

src/2023/Day09.cpp

@@ -18,7 +18,8 @@ namespace y2023::day09
       std::vector<int> numbers;
       std::stringstream ss{str};
       int i;
-      while (ss >> i) numbers.emplace_back(i);
+      while (ss >> i)
+        numbers.emplace_back(i);
 
       ints.emplace_back(numbers);
     }

src/2024/Day03.cpp

@@ -26,7 +26,8 @@ namespace y2024::day03
   {
     int32_t sum = 0;
     std::vector<std::string> matches = Helper::GetAllRegexMatches(input, "mul\\([0-9]*,[0-9]*\\)");
-    for (auto& str : matches) sum += Mult(str);
+    for (auto& str : matches)
+      sum += Mult(str);
     return sum;
   }
 

src/2024/Day07.cpp

@@ -50,7 +50,8 @@ namespace y2024::day07
   int64_t Concat(int64_t i1, int64_t i2)
   {
     int64_t base = 10;
-    while (i2 >= base) base *= 10;
+    while (i2 >= base)
+      base *= 10;
     return i1 * base + i2;
   }
 

src/2024/Day11.cpp

@@ -13,7 +13,8 @@ namespace y2024::day11
   READ_INPUT(input)
   {
     Stones stones;
-    for (auto i : Input::ReadInt64s(input, ' ')) stones[i]++;
+    for (auto i : Input::ReadInt64s(input, ' '))
+      stones[i]++;
     return stones;
   }
 
@@ -33,7 +34,8 @@ namespace y2024::day11
   {
     int64_t pow = 1;
 
-    for (int j = 0; j < i; j++) pow *= 10;
+    for (int j = 0; j < i; j++)
+      pow *= 10;
 
     return pow;
   }
@@ -74,7 +76,8 @@ namespace y2024::day11
   {
     std::map<int64_t, int64_t> cpy = stones;
 
-    for (int i = 0; i < iterations; i++) Step(cpy);
+    for (int i = 0; i < iterations; i++)
+      Step(cpy);
 
     int64_t sum = 0;
     for (auto& [cur, count] : cpy)

src/2024/Day15.cpp

@@ -21,7 +21,8 @@ namespace y2024::day15
     map.map = Input::ReadArray2D(input);
 
     std::string str;
-    while (std::getline(input, str)) map.input += str;
+    while (std::getline(input, str))
+      map.input += str;
 
     return map;
   }

src/2024/Day16.cpp

@@ -48,7 +48,8 @@ namespace y2024::day16
       Helper::DijkstrasAllVisited(input, std::pair{input.Find('S'), Index2D{1, 0}}, Branch, Goal);
 
     std::set<Index2D> solutions;
-    for (const auto& [pos, dir] : allVisited) solutions.emplace(pos);
+    for (const auto& [pos, dir] : allVisited)
+      solutions.emplace(pos);
 
     return solutions.size();
   }

src/2024/Day23.cpp

@@ -92,13 +92,15 @@ namespace y2024::day23
       FindLargest(input, computers, largest);
     }
 
-    for (const auto& s : largest) std::cout << s << ",";
+    for (const auto& s : largest)
+      std::cout << s << ",";
     std::cout << std::endl;
 
     // Some arbitrary solution number to have some form of verification in the code.
     // Sum all letters of the computers (with a=0, b=1, etc)
     int64_t sum = 0;
-    for (const auto& s : largest) sum += (s[0] - 'a') + (s[1] - 'a');
+    for (const auto& s : largest)
+      sum += (s[0] - 'a') + (s[1] - 'a');
 
     return sum;
   }

src/common/aoc.h

@@ -30,6 +30,7 @@
 #include "common/lib/Json.h"
 #include "common/lib/Mapper.h"
 #include "common/lib/Math.h"
+#include "common/lib/Md5.h"
 #include "common/lib/Timer.h"
 
 #define TERM_RED "\x1B[31m"

src/common/lib/Array2D.h

@@ -9,6 +9,20 @@ struct Index2D
   int x = -1;
   int y = -1;
 
+  void RotateCW()
+  {
+    int tmp = y;
+    y = x;
+    x = -tmp;
+  }
+
+  void RotateCCW()
+  {
+    int tmp = y;
+    y = -x;
+    x = tmp;
+  }
+
   bool IsValid()
   {
     return x != -1 && y != -1;
@@ -494,6 +508,7 @@ struct Array2D
       {
         os << array2D.Get(x, y);
       }
+      if (y != array2D.height - 1)
         os << std::endl;
     }
     return std::cout;

src/common/lib/Helper.cpp

@@ -0,0 +1,249 @@
+#include "Helper.h"
+
+#include <regex>
+
+inline bool Helper::traceErrors = true;
+
+Helper::ScopedTraceErrorDisabler::ScopedTraceErrorDisabler()
+{
+  DisableTraceErrors();
+}
+
+Helper::ScopedTraceErrorDisabler::~ScopedTraceErrorDisabler()
+{
+  ResetTraceErrors();
+}
+
+std::vector<std::string_view> Helper::Split(const std::string& str, const std::string& delim)
+{
+  std::vector<std::string_view> split;
+  size_t pos = str.find(delim);
+  size_t lastPos = 0;
+  while (pos != std::string::npos)
+  {
+    split.emplace_back(std::string_view{str.c_str() + lastPos, pos - lastPos});
+    lastPos = pos + delim.size();
+    pos = str.find(delim, pos + delim.size());
+  }
+  split.emplace_back(std::string_view{str.c_str() + lastPos, str.size() - lastPos});
+  return split;
+}
+
+bool Helper::StartsWith(const std::string_view& str, const std::string& prefix, size_t offset)
+{
+  return str.substr(offset, prefix.size()) == prefix;
+}
+
+bool Helper::EndsWith(const std::string_view& str, const std::string& prefix)
+{
+  return str.substr(str.size() - prefix.size(), prefix.size()) == prefix;
+}
+
+void Helper::Replace(std::string& str, size_t size, const std::string& other, size_t pos)
+{
+  str.replace(pos, size, other);
+}
+
+bool Helper::IsDigit(char c)
+{
+  return c >= '0' && c <= '9';
+}
+
+int Helper::GetNumberOfDigits(int n)
+{
+  assert(n > 0);
+  // clang-format off
+    if (n < 10)            return 1;
+    if (n < 100)           return 2;
+    if (n < 1'000)         return 3;
+    if (n < 10'000)        return 4;
+    if (n < 100'000)       return 5;
+    if (n < 1'000'000)     return 6;
+    if (n < 10'000'000)    return 7;
+    if (n < 100'000'000)   return 8;
+    if (n < 1'000'000'000) return 9;
+  // clang-format on
+  return 10;
+}
+
+int Helper::GetNumberOfDigits(int64_t n)
+{
+  assert(n > 0);
+  // clang-format off
+    if (n < 10)                        return 1;
+    if (n < 100)                       return 2;
+    if (n < 1'000)                     return 3;
+    if (n < 10'000)                    return 4;
+    if (n < 100'000)                   return 5;
+    if (n < 1'000'000)                 return 6;
+    if (n < 10'000'000)                return 7;
+    if (n < 100'000'000)               return 8;
+    if (n < 1'000'000'000)             return 9;
+    if (n < 10'000'000'000)            return 10;
+    if (n < 100'000'000'000)           return 11;
+    if (n < 1'000'000'000'000)         return 12;
+    if (n < 10'000'000'000'000)        return 13;
+    if (n < 100'000'000'000'000)       return 14;
+    if (n < 1'000'000'000'000'000)     return 15;
+    if (n < 10'000'000'000'000'000)    return 16;
+    if (n < 100'000'000'000'000'000)   return 17;
+    if (n < 1'000'000'000'000'000'000) return 18;
+  // clang-format on
+  return 19;
+}
+
+int64_t Helper::Pow10(int pow)
+{
+  int64_t p = 10;
+  for (int i = 1; i < pow; i++)
+  {
+    p *= 10;
+  }
+  return p;
+}
+
+int Helper::BinStrToInt(const std::string& str)
+{
+  if (str.size() >= 32)
+  {
+    std::cout << "BinStrToInt: Too big string, use BinStrToInt64 instead" << std::endl;
+    return 0;
+  }
+
+  int val = 0;
+  for (size_t i = 0; i < str.size(); i++)
+  {
+    if (str[i] == '1')
+      val |= (1 << (str.size() - i - 1));
+  }
+  return val;
+}
+
+int64_t Helper::BinStrToInt64(const std::string& str)
+{
+  if (str.size() >= 64)
+  {
+    std::cout << "BinStrToInt64: Too big string" << std::endl;
+    return 0;
+  }
+
+  int64_t val = 0;
+  for (size_t i = 0; i < str.size(); i++)
+  {
+    if (str[i] == '1')
+      val |= (1ll << (str.size() - i - 1));
+  }
+  return val;
+}
+
+std::string Helper::Repeat(const std::string& str, int count)
+{
+  std::string s;
+  for (int i = 0; i < count; i++)
+  {
+    s += str;
+  }
+  return s;
+}
+
+std::vector<std::string> Helper::GetAllRegexMatches(const std::string& str, const std::string& regex)
+{
+  std::vector<std::string> matches;
+  std::regex reg{regex};
+  auto it = std::sregex_iterator(str.begin(), str.end(), reg);
+  auto end = std::sregex_iterator();
+  for (; it != end; it++)
+  {
+    matches.emplace_back(it->str());
+  }
+  return matches;
+}
+
+std::vector<Index2D> Helper::GetNeighborDirections()
+{
+  return std::vector<Index2D>{Index2D{1, 0}, Index2D{0, 1}, Index2D{-1, 0}, Index2D{0, -1}};
+}
+
+Index2D Helper::GetDirection(char c)
+{
+  if (c == 'v' || c == 'V')
+    return Index2D{0, 1};
+  if (c == '^')
+    return Index2D{0, -1};
+  if (c == '>')
+    return Index2D{1, 0};
+  if (c == '<')
+    return Index2D{-1, 0};
+  std::cerr << "GetDirection: Invalid char: " << c << std::endl;
+  return Index2D{-1, -1};
+}
+
+int64_t Helper::ChineseRemainderTheoremTwo(int64_t mod1, int64_t mod2, int64_t remainder1, int64_t remainder2)
+{
+  int64_t i = remainder1;
+  while (true)
+  {
+    if (i % mod2 == remainder2)
+      return i;
+
+    i += mod1;
+  }
+  return 0;
+}
+
+int64_t Helper::ChineseRemainderTheorem(const std::vector<int64_t>& mods, const std::vector<int64_t>& remainders)
+{
+  int64_t currentMod = mods.front();
+  int64_t currentRem = remainders.front();
+  for (int i = 1; i < mods.size(); i++)
+  {
+    int64_t result = ChineseRemainderTheoremTwo(currentMod, mods[i], currentRem, remainders[i]);
+    currentRem = result;
+    currentMod = currentMod * mods[i];
+  }
+  return currentRem;
+}
+
+int64_t Helper::ChineseRemainderTheorem(const std::vector<int64_t>& mods,
+                                        std::vector<int64_t> remainders,
+                                        const std::vector<int64_t>& starts)
+{
+  for (int i = 0; i < mods.size(); i++)
+  {
+    remainders[i] = ((remainders[i] - starts[i]) % mods[i] + mods[i]) % mods[i];
+  }
+  return ChineseRemainderTheorem(mods, remainders);
+}
+
+uint64_t Helper::FastExponentiation(uint64_t start, uint64_t multiplication, uint64_t power, uint64_t mod)
+{
+  while (power > 0)
+  {
+    if (power % 2 == 0)
+    {
+      multiplication = (multiplication * multiplication) % mod;
+      power /= 2;
+    }
+    else
+    {
+      start = (start * multiplication) % mod;
+      power--;
+    }
+  }
+  return start;
+}
+
+int64_t Helper::ManhattanDistance(const Index2D& from, const Index2D& to)
+{
+  return std::abs(from.x - to.x) + std::abs(from.y - to.y);
+}
+
+void Helper::DisableTraceErrors()
+{
+  traceErrors = false;
+}
+
+void Helper::ResetTraceErrors()
+{
+  traceErrors = true;
+}

src/common/lib/Helper.h

@@ -4,12 +4,12 @@
 
 #include <algorithm>
 #include <array>
+#include <deque>
 #include <functional>
 #include <iostream>
 #include <limits>
 #include <map>
 #include <numeric>
-#include <regex>
 #include <set>
 #include <vector>
 
@@ -18,11 +18,14 @@
 
 #define BIT(x) (1 << (x))
 
-template <typename T>
+template <typename... Args>
-static std::ostream& operator<<(std::ostream& stream, const std::vector<T>& container);
+static std::ostream& operator<<(std::ostream& stream, const std::vector<Args...>& container);
 
-template <typename T>
+template <typename... Args>
-static std::ostream& operator<<(std::ostream& stream, const std::set<T>& container);
+static std::ostream& operator<<(std::ostream& stream, const std::deque<Args...>& container);
+
+template <typename... Args>
+static std::ostream& operator<<(std::ostream& stream, const std::set<Args...>& container);
 
 template <typename T, typename S>
 static std::ostream& operator<<(std::ostream& stream, const std::map<T, S>& container);
@@ -34,15 +37,8 @@ struct Helper
 {
   struct ScopedTraceErrorDisabler
   {
-    ScopedTraceErrorDisabler()
+    ScopedTraceErrorDisabler();
-    {
+    ~ScopedTraceErrorDisabler();
-      DisableTraceErrors();
-    }
-
-    ~ScopedTraceErrorDisabler()
-    {
-      ResetTraceErrors();
-    }
   };
 
   template <typename T, typename S>
@@ -51,114 +47,21 @@ struct Helper
     t.erase(std::remove_if(t.begin(), t.end(), func), t.end());
   }
 
-  static bool StartsWith(const std::string_view& str, const std::string& prefix, size_t offset = 0)
+  static std::vector<std::string_view> Split(const std::string& str, const std::string& delim);
-  {
+  static bool StartsWith(const std::string_view& str, const std::string& prefix, size_t offset = 0);
-    return str.substr(offset, prefix.size()) == prefix;
+  static bool EndsWith(const std::string_view& str, const std::string& prefix);
-  }
+  static void Replace(std::string& str, size_t size, const std::string& other, size_t pos);
 
-  static bool EndsWith(const std::string_view& str, const std::string& prefix)
+  static bool IsDigit(char c);
-  {
+  static int GetNumberOfDigits(int n);
-    return str.substr(str.size() - prefix.size(), prefix.size()) == prefix;
+  static int GetNumberOfDigits(int64_t n);
-  }
+  static int64_t Pow10(int pow);
-
-  static void Replace(std::string& str, size_t size, const std::string& other, size_t pos)
-  {
-    str.replace(pos, size, other);
-  }
-
-  static bool IsDigit(char c)
-  {
-    return c >= '0' && c <= '9';
-  }
-
-  static int GetNumberOfDigits(int n)
-  {
-    assert(n > 0);
-    // clang-format off
-    if (n < 10)            return 1;
-    if (n < 100)           return 2;
-    if (n < 1'000)         return 3;
-    if (n < 10'000)        return 4;
-    if (n < 100'000)       return 5;
-    if (n < 1'000'000)     return 6;
-    if (n < 10'000'000)    return 7;
-    if (n < 100'000'000)   return 8;
-    if (n < 1'000'000'000) return 9;
-    // clang-format on
-    return 10;
-  }
-
-  static int GetNumberOfDigits(int64_t n)
-  {
-    assert(n > 0);
-    // clang-format off
-    if (n < 10)                        return 1;
-    if (n < 100)                       return 2;
-    if (n < 1'000)                     return 3;
-    if (n < 10'000)                    return 4;
-    if (n < 100'000)                   return 5;
-    if (n < 1'000'000)                 return 6;
-    if (n < 10'000'000)                return 7;
-    if (n < 100'000'000)               return 8;
-    if (n < 1'000'000'000)             return 9;
-    if (n < 10'000'000'000)            return 10;
-    if (n < 100'000'000'000)           return 11;
-    if (n < 1'000'000'000'000)         return 12;
-    if (n < 10'000'000'000'000)        return 13;
-    if (n < 100'000'000'000'000)       return 14;
-    if (n < 1'000'000'000'000'000)     return 15;
-    if (n < 10'000'000'000'000'000)    return 16;
-    if (n < 100'000'000'000'000'000)   return 17;
-    if (n < 1'000'000'000'000'000'000) return 18;
-    // clang-format on
-    return 19;
-  }
-
-  static int64_t Pow10(int pow)
-  {
-    int64_t p = 10;
-    for (int i = 1; i < pow; i++)
-    {
-      p *= 10;
-    }
-    return p;
-  }
 
   // Converts a binary string to an int32_t ie "10100111001" to 1337
-  static int BinStrToInt(const std::string& str)
+  static int BinStrToInt(const std::string& str);
-  {
-    if (str.size() >= 32)
-    {
-      std::cout << "BinStrToInt: Too big string, use BinStrToInt64 instead" << std::endl;
-      return 0;
-    }
-
-    int val = 0;
-    for (size_t i = 0; i < str.size(); i++)
-    {
-      if (str[i] == '1')
-        val |= (1 << (str.size() - i - 1));
-    }
-    return val;
-  }
 
   // Converts a binary string to an int64_t ie "10100111001" to 1337
-  static int64_t BinStrToInt64(const std::string& str)
+  static int64_t BinStrToInt64(const std::string& str);
-  {
-    if (str.size() >= 64)
-    {
-      std::cout << "BinStrToInt64: Too big string" << std::endl;
-      return 0;
-    }
-
-    int64_t val = 0;
-    for (size_t i = 0; i < str.size(); i++)
-    {
-      if (str[i] == '1')
-        val |= (1ll << (str.size() - i - 1));
-    }
-    return val;
-  }
 
   template <typename T, typename S>
   static T Sum(const S& container)
@@ -298,7 +201,8 @@ struct Helper
   {
     std::map<State, int> visited;
     std::multimap<int, std::pair<int, State>> open;
-    for (int i = 0; i < initial.size(); i++) open.emplace(0, std::pair<int, State>{0, initial[i]});
+    for (int i = 0; i < initial.size(); i++)
+      open.emplace(0, std::pair<int, State>{0, initial[i]});
     while (!open.empty())
     {
       auto it = open.begin();
@@ -340,7 +244,8 @@ struct Helper
   {
     std::map<State, int> visited;
     std::multimap<int, std::pair<int, std::vector<State>>> open;
-    for (int i = 0; i < initial.size(); i++) open.emplace(0, std::pair<int, std::vector<State>>{0, {initial[i]}});
+    for (int i = 0; i < initial.size(); i++)
+      open.emplace(0, std::pair<int, std::vector<State>>{0, {initial[i]}});
     while (!open.empty())
     {
       const auto& [heuristicVal, state] = *open.begin();
@@ -527,15 +432,7 @@ struct Helper
     return stream;
   }
 
-  static std::string Repeat(const std::string& str, int count)
+  static std::string Repeat(const std::string& str, int count);
-  {
-    std::string s;
-    for (int i = 0; i < count; i++)
-    {
-      s += str;
-    }
-    return s;
-  }
 
   template <typename T>
   static std::vector<T> Repeat(const std::vector<T>& vec, int count)
@@ -551,81 +448,27 @@ struct Helper
     return ret;
   }
 
-  static std::vector<std::string> GetAllRegexMatches(const std::string& str, const std::string& regex)
+  static std::vector<std::string> GetAllRegexMatches(const std::string& str, const std::string& regex);
-  {
-    std::vector<std::string> matches;
-    std::regex reg{regex};
-    auto it = std::sregex_iterator(str.begin(), str.end(), reg);
-    auto end = std::sregex_iterator();
-    for (; it != end; it++)
-    {
-      matches.emplace_back(it->str());
-    }
-    return matches;
-  }
 
-  static std::vector<Index2D> GetNeighborDirections()
+  static std::vector<Index2D> GetNeighborDirections();
-  {
+  static Index2D GetDirection(char c);
-    return std::vector<Index2D>{Index2D{1, 0}, Index2D{0, 1}, Index2D{-1, 0}, Index2D{0, -1}};
-  }
 
-  static Index2D GetDirection(char c)
+  // Solve for N:
-  {
+  // remainder1 = N % mod1
-    if (c == 'v' || c == 'V')
+  // remainder2 = N % mod2
-      return Index2D{0, 1};
+  static int64_t ChineseRemainderTheoremTwo(int64_t mod1, int64_t mod2, int64_t remainder1, int64_t remainder2);
-    if (c == '^')
-      return Index2D{0, -1};
-    if (c == '>')
-      return Index2D{1, 0};
-    if (c == '<')
-      return Index2D{-1, 0};
-    std::cerr << "GetDirection: Invalid char: " << c << std::endl;
-    return Index2D{-1, -1};
-  }
 
-  static int64_t ChineseRemainderTheoremTwo(int64_t mod1, int64_t mod2, int64_t res1, int64_t res2)
+  // Solve for N:
-  {
+  // remainders = N % mods
-    int64_t i = res1;
+  static int64_t ChineseRemainderTheorem(const std::vector<int64_t>& mods, const std::vector<int64_t>& remainders);
-    while (true)
-    {
-      if (i % mod2 == res2)
-        return i;
 
-      i += mod1;
+  // Solve for N:
-    }
+  // remainders = (start + N) % mods
-    return 0;
+  static int64_t ChineseRemainderTheorem(const std::vector<int64_t>& mods,
-  }
+                                         std::vector<int64_t> remainders,
+                                         const std::vector<int64_t>& starts);
 
-  static int64_t ChineseRemainderTheorem(const std::vector<int64_t>& mods, const std::vector<int64_t>& results)
+  static uint64_t FastExponentiation(uint64_t start, uint64_t multiplication, uint64_t power, uint64_t mod);
-  {
-    int64_t currentMod = mods.front();
-    int64_t currentRes = results.front();
-    for (int i = 1; i < mods.size(); i++)
-    {
-      int64_t result = ChineseRemainderTheoremTwo(currentMod, mods[i], currentRes, results[i]);
-      currentRes = result;
-      currentMod = currentMod * mods[i];
-    }
-    return currentRes;
-  }
-
-  static uint64_t FastExponentiation(uint64_t start, uint64_t multiplication, uint64_t power, uint64_t mod)
-  {
-    while (power > 0)
-    {
-      if (power % 2 == 0)
-      {
-        multiplication = (multiplication * multiplication) % mod;
-        power /= 2;
-      }
-      else
-      {
-        start = (start * multiplication) % mod;
-        power--;
-      }
-    }
-    return start;
-  }
 
   // Input    - Puzzle input
   // Function - bool(int64_t);
@@ -652,20 +495,11 @@ struct Helper
       return BinarySearch(input, min, i - 1, func);
   }
 
-  static int64_t ManhattanDistance(const Index2D& from, const Index2D& to)
+  static int64_t ManhattanDistance(const Index2D& from, const Index2D& to);
-  {
-    return std::abs(from.x - to.x) + std::abs(from.y - to.y);
-  }
 
-  static void DisableTraceErrors()
+  static void DisableTraceErrors();
-  {
-    traceErrors = false;
-  }
 
-  static void ResetTraceErrors()
+  static void ResetTraceErrors();
-  {
-    traceErrors = true;
-  }
 
 private:
   template <typename Key, typename Value, typename Compare, typename Eval>
@@ -728,16 +562,20 @@ public:
   static bool traceErrors;
 };
 
-inline bool Helper::traceErrors = true;
+template <typename... Args>
-
+static std::ostream& operator<<(std::ostream& stream, const std::vector<Args...>& container)
-template <typename T>
-static std::ostream& operator<<(std::ostream& stream, const std::vector<T>& container)
 {
   return Helper::Print(stream, container);
 }
 
-template <typename T>
+template <typename... Args>
-static std::ostream& operator<<(std::ostream& stream, const std::set<T>& container)
+static std::ostream& operator<<(std::ostream& stream, const std::deque<Args...>& container)
+{
+  return Helper::Print(stream, container);
+}
+
+template <typename... Args>
+static std::ostream& operator<<(std::ostream& stream, const std::set<Args...>& container)
 {
   return Helper::Print(stream, container);
 }

src/common/lib/Input.h

@@ -3,6 +3,7 @@
 #include <stdint.h>
 
 #include <iostream>
+#include <sstream>
 #include <string>
 
 #include "Array2D.h"
@@ -12,9 +13,11 @@
 static std::istream& operator>>(std::istream& stream, char const* pattern)
 {
   char c;
-  while (stream.peek() == ' ') stream.get(c);
+  while (stream.peek() == ' ')
+    stream.get(c);
 
-  while (*pattern != '\0' && stream && *pattern == stream.peek() && stream.get(c)) ++pattern;
+  while (*pattern != '\0' && stream && *pattern == stream.peek() && stream.get(c))
+    ++pattern;
 
   if (*pattern != '\0')
     stream.setstate(std::ios::failbit);
@@ -36,7 +39,8 @@ struct Input
         break;
       width = (int)str.length();
       height++;
-      for (auto c : str) data.emplace_back(c);
+      for (auto c : str)
+        data.emplace_back(c);
     }
     return Array2D<char>(width, height, data);
   }
@@ -51,7 +55,30 @@ struct Input
     {
       width = (int)str.length();
       height++;
-      for (auto c : str) data.emplace_back(c - '0');
+      for (auto c : str)
+        data.emplace_back(c - '0');
+    }
+    return Array2D<int>(width, height, data);
+  }
+
+  static Array2D<int> ReadIntsAsArray2D(std::istream& input)
+  {
+    std::vector<int> data;
+    int width = 0;
+    int height = 0;
+    std::string str;
+    while (getline(input, str))
+    {
+      height++;
+      std::stringstream ss{str};
+      int i;
+      int size = 0;
+      while (ss >> i)
+      {
+        data.emplace_back(i);
+        size++;
+      }
+      width = size;
     }
     return Array2D<int>(width, height, data);
   }
@@ -70,7 +97,8 @@ struct Input
   {
     std::vector<int> ints;
     std::string str;
-    while (getline(input, str, delimiter)) ints.emplace_back(std::atoi(str.c_str()));
+    while (getline(input, str, delimiter))
+      ints.emplace_back(std::atoi(str.c_str()));
     return ints;
   }
 
@@ -78,7 +106,8 @@ struct Input
   {
     std::vector<int64_t> ints;
     std::string str;
-    while (getline(input, str, delimiter)) ints.emplace_back(std::atoll(str.c_str()));
+    while (getline(input, str, delimiter))
+      ints.emplace_back(std::atoll(str.c_str()));
     return ints;
   }
 
@@ -86,7 +115,8 @@ struct Input
   {
     std::vector<std::string> strings;
     std::string str;
-    while (getline(input, str)) strings.emplace_back(str);
+    while (getline(input, str))
+      strings.emplace_back(str);
     return strings;
   }
 
@@ -94,7 +124,8 @@ struct Input
   {
     std::string result;
     std::string str;
-    while (getline(input, str)) result += str + '\n';
+    while (getline(input, str))
+      result += str + '\n';
     if (!result.empty())
       result.pop_back();
     return result;

src/common/lib/JsonUtil.cpp

@@ -97,7 +97,8 @@ bool JsonUtil::ReadString(const std::string& str, uint64_t& pos, Json& json)
   uint64_t stringStart = pos;
   while (true)
   {
-    while (pos < str.size() && str[pos] != '\"') pos++;
+    while (pos < str.size() && str[pos] != '\"')
+      pos++;
     if (pos >= str.size() || str[pos - 1] != '\\')
       break;
   }

src/common/lib/Md5.cpp

@@ -0,0 +1,170 @@
+#include "common/lib/Md5.h"
+
+#include <array>
+#include <cstring>
+#include <iomanip>
+#include <iostream>
+
+#undef AOC_MD5_TESTING
+
+void PrintData(uint8_t* data)
+{
+  for (int i = 0; i < 8; i++)
+  {
+    for (int j = 0; j < 8; j++)
+    {
+      std::cout << std::hex << std::setw(2) << std::setfill('0') << (int)data[i * 8 + j];
+    }
+    std::cout << " ";
+    for (int j = 0; j < 8; j++)
+    {
+      if (data[i * 8 + j] >= 32 && data[i * 8 + j] < 126)
+        std::cout << data[i * 8 + j];
+      else
+        std::cout << "?";
+    }
+    std::cout << std::endl;
+  }
+
+  std::cout << std::dec << std::endl;
+}
+
+uint32_t Md5::BytesToUint32(uint8_t* data)
+{
+  return ((uint32_t)data[3] << 24) | ((uint32_t)data[2] << 16) | ((uint32_t)data[1] << 8) | (uint32_t)data[0];
+}
+
+uint32_t Md5::LeftRotate(uint32_t x, uint32_t n)
+{
+  return (x << n) | (x >> (32 - n));
+}
+
+void Md5::Transform(uint8_t* data, uint32_t& a0, uint32_t& b0, uint32_t& c0, uint32_t& d0)
+{
+#ifdef AOC_MD5_TESTING
+  PrintData(data);
+#endif
+  // clang-format off
+  const static std::array<uint32_t, 64> K
+  {
+    0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
+    0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
+    0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
+    0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
+    0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
+    0xd62f105d, 0x02441453, 0xd8a1e681, 0xe7d3fbc8,
+    0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
+    0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
+    0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
+    0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
+    0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x04881d05,
+    0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
+    0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
+    0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
+    0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
+    0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
+  };
+  const static std::array<uint32_t, 64> S
+  {
+    7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22, 7, 12, 17, 22,
+    5,  9, 14, 20, 5,  9, 14, 20, 5,  9, 14, 20, 5,  9, 14, 20,
+    4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23, 4, 11, 16, 23,
+    6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21, 6, 10, 15, 21
+  };
+  // clang-format on
+
+  uint32_t A = a0;
+  uint32_t B = b0;
+  uint32_t C = c0;
+  uint32_t D = d0;
+
+  for (int i = 0; i < 64; i++)
+  {
+    uint32_t F;
+    uint32_t g;
+    if (i < 16)
+    {
+      F = (B & C) | ((~B) & D);
+      g = i;
+    }
+    else if (i < 32)
+    {
+      F = (D & B) | ((~D) & C);
+      g = (5 * i + 1) % 16;
+    }
+    else if (i < 48)
+    {
+      F = B ^ C ^ D;
+      g = (3 * i + 5) % 16;
+    }
+    else
+    {
+      F = C ^ (B | (~D));
+      g = (7 * i) % 16;
+    }
+    F = F + A + K[i] + BytesToUint32(data + g * 4);
+    A = D;
+    D = C;
+    C = B;
+    B = B + LeftRotate(F, S[i]);
+  }
+  a0 += A;
+  b0 += B;
+  c0 += C;
+  d0 += D;
+}
+
+void Md5::PrintUint32(std::ostream& os, uint32_t n)
+{
+  os << std::hex;
+  os << std::setw(2) << std::setfill('0') << (n & 0xff);
+  os << std::setw(2) << std::setfill('0') << ((n >> 8) & 0xff);
+  os << std::setw(2) << std::setfill('0') << ((n >> 16) & 0xff);
+  os << std::setw(2) << std::setfill('0') << ((n >> 24) & 0xff);
+  os << std::dec;
+}
+
+std::string Md5::Hash(std::string str)
+{
+  str += 0x80;
+
+  uint32_t a0 = 0x67452301;
+  uint32_t b0 = 0xefcdab89;
+  uint32_t c0 = 0x98badcfe;
+  uint32_t d0 = 0x10325476;
+
+  uint64_t size = str.size();
+  uint64_t bytesToAdd = (64 + 56 - (size % 64)) % 64;
+
+  // std::cout << str.size() << " " << bytesToAdd << std::endl;
+  int loops = (size + bytesToAdd + 8) / 64;
+  if ((size + bytesToAdd + 8) % 64 != 0)
+    loops++;
+  uint64_t offset = 0;
+  for (int i = 0; i < loops - 1; i++)
+  {
+    uint8_t data[64];
+    std::memset(data, 0x0, 64);
+    std::memcpy(data, str.c_str() + offset, std::min<int>(str.size() - offset, 64));
+    Transform(data, a0, b0, c0, d0);
+    offset += 64;
+  }
+
+  uint8_t data[64];
+  std::memset(data, 0x0, 64);
+  if (str.size() >= offset)
+    std::memcpy(data, str.c_str() + offset, str.size() - offset);
+  for (int i = 0; i < 8; i++)
+  {
+    data[56 + i] = (((str.size() - 1) * 8) >> (i * 8)) & 0xff;
+  }
+
+  Transform(data, a0, b0, c0, d0);
+
+  std::stringstream ss{};
+  PrintUint32(ss, a0);
+  PrintUint32(ss, b0);
+  PrintUint32(ss, c0);
+  PrintUint32(ss, d0);
+  return ss.str();
+}

src/common/lib/Md5.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <stdint.h>
+
+#include <string>
+
+class Md5
+{
+public:
+  static std::string Hash(std::string str);
+
+private:
+  static uint32_t BytesToUint32(uint8_t* data);
+  static uint32_t LeftRotate(uint32_t x, uint32_t n);
+  static void Transform(uint8_t* data, uint32_t& a0, uint32_t& b0, uint32_t& c0, uint32_t& d0);
+  static void PrintUint32(std::ostream& os, uint32_t n);
+};