Add solution for 2016 Day 24

res/2016/day24/test_input.txt

@@ -0,0 +1,5 @@
+###########
+#0.1.....2#
+#.#######.#
+#4.......3#
+###########

src/2016/Day24.cpp

@@ -2,30 +2,77 @@
 
 namespace y2016::day24
 {
-  REGISTER_DAY(2016, Day24, std::vector<int>, int);
+  REGISTER_DAY(2016, Day24, Array2D<char>, 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);
+  REGISTER_TEST_EXAMPLE(2016, Day24, ExampleInput, 1, 14);
+  REGISTER_TEST(2016, Day24, Input, 1, 448);
+  REGISTER_TEST_EXAMPLE(2016, Day24, ExampleInput, 2, 20);
+  REGISTER_TEST(2016, Day24, Input, 2, 672);
 
   READ_INPUT(input)
   {
-    std::vector<int> vec;
-    std::string str;
-    while (getline(input, str))
+    return Input::ReadArray2D(input);
+  }
+
+  struct State
+  {
+    Index2D pos;
+    char goalChar;
+
+    bool operator<(const State& other) const
     {
+      return pos < other.pos;
     }
-    return vec;
+  };
+
+  std::vector<std::pair<int, State>> Branch(const Array2D<char>& map, const State& state)
+  {
+    std::vector<std::pair<int, State>> branches;
+    for (const auto& pos : map.GetNeighbors(state.pos, false))
+    {
+      if (map[pos] != '#')
+        branches.emplace_back(1, State{pos, state.goalChar});
+    }
+    return branches;
+  }
+
+  bool Goal(const Array2D<char>& map, const State& state)
+  {
+    return map[state.pos] == state.goalChar;
+  }
+
+  Graph<char, int> GetGraph(const Array2D<char>& map)
+  {
+    std::vector<Index2D> positions(10);
+    for (auto it = map.begin(); it != map.end(); it++)
+    {
+      if (*it >= '0' && *it <= '9')
+      {
+        positions[*it - '0'] = it.index;
+      }
+    }
+    while (!positions.back().IsValid())
+      positions.pop_back();
+
+    Graph<char, int> graph;
+    for (size_t i = 0; i < positions.size(); i++)
+    {
+      for (size_t j = i + 1; j < positions.size(); j++)
+      {
+        int distance = Helper::Dijkstras(map, State{positions[i], (char)(j + '0')}, Branch, Goal);
+        graph.AddTwoWayEdge(i + '0', j + '0', distance);
+      }
+    }
+    return graph;
   }
 
   OUTPUT1(input)
   {
-    return 0;
+    return Helper::TSP(GetGraph(input), '0', false);
   }
 
   OUTPUT2(input)
   {
-    return 0;
+    return Helper::TSP(GetGraph(input), '0', true);
   }
 }

src/common/lib/Graph.h

@@ -106,6 +106,11 @@ public:
     return graph.find(from)->second.find(to)->second;
   }
 
+  const std::map<Key, std::map<Key, Value>>& GetGraph() const
+  {
+    return graph;
+  }
+
   const std::map<Key, Value>& GetPaths(const Key& from) const
   {
     return graph.find(from)->second;

src/common/lib/Helper.h

@@ -506,17 +506,29 @@ struct Helper
   static void ResetTraceErrors();
 
 private:
-  template <typename Key, typename Value, typename Compare, typename Eval>
+  template <typename Key, typename Value>
+  static Value TSPCalculatePath(const Graph<Key, Value>& graph, const std::vector<Key>& path, bool returnToStart)
+  {
+    int cost = 0;
+    for (int i = 0; i < path.size() - 1; i++)
+    {
+      cost += graph.GetEdge(path[i], path[i + 1]);
+    }
+
+    if (returnToStart)
+      cost += graph.GetEdge(path.back(), path.front());
+
+    return cost;
+  }
+
+  template <typename Key, typename Value>
   static int TSP(const Graph<Key, Value>& graph,
                  const std::set<Key>& nodesLeft,
                  const std::vector<Key>& order,
-                 Compare compare,
-                 Eval eval)
+                 bool returnToStart)
   {
     if (nodesLeft.empty())
-    {
-      return eval(graph, order);
-    }
+      return TSPCalculatePath(graph, order, returnToStart);
 
     bool hasSet = false;
     Value tsp;
@@ -528,9 +540,9 @@ private:
       std::vector<Key> newOrder = order;
       newOrder.emplace_back(node);
       if (hasSet)
-        tsp = compare(tsp, TSP(graph, newNodesLeft, newOrder, compare, eval));
+        tsp = std::min(tsp, TSP(graph, newNodesLeft, newOrder, returnToStart));
       else
-        tsp = TSP(graph, newNodesLeft, newOrder, compare, eval);
+        tsp = TSP(graph, newNodesLeft, newOrder, returnToStart);
       hasSet = true;
     }
     return tsp;
@@ -539,28 +551,20 @@ private:
 public:
   // Key     - Node type of the graph
   // Value   - Edge type of the graph
-  // Compare - Value(Value, Value)
-  //           Given two solutions, which one is better
-  // Eval    - int(const Graph&, const std::vector<Key>&)
-  //           Given the graph and order of the TSP, what is the total cost
-  template <typename Key, typename Value, typename Compare, typename Eval>
-  static int TSP(const Graph<Key, Value>& graph, const Key& start, Compare compare, Eval eval)
+  template <typename Key, typename Value>
+  static int TSP(const Graph<Key, Value>& graph, const Key& start, bool returnToStart)
   {
     std::set<Key> nodes = graph.GetNodes();
     nodes.erase(nodes.find(start));
-    return TSP(graph, nodes, std::vector<Key>{start}, compare, eval);
+    return TSP(graph, nodes, std::vector<Key>{start}, returnToStart);
   }
 
   // Key     - Node type of the graph
   // Value   - Edge type of the graph
-  // Compare - Value(Value, Value)
-  //           Given two solutions, which one is better
-  // Eval    - int(const Graph&, const std::vector<Key>&)
-  //           Given the graph and order of the TSP, what is the total cost
-  template <typename Key, typename Value, typename Compare, typename Eval>
-  static int TSP(const Graph<Key, Value>& graph, Compare compare, Eval eval)
+  template <typename Key, typename Value>
+  static int TSP(const Graph<Key, Value>& graph, bool returnToStart)
   {
-    return TSP(graph, graph.GetNodes(), std::vector<Key>{}, compare, eval);
+    return TSP(graph, graph.GetNodes(), std::vector<Key>{}, returnToStart);
   }
 
   static bool traceErrors;