Initial commit with solutions from 2024

2025-11-26 21:59:50 +01:00
commit be113565fb
72 changed files with 7030 additions and 0 deletions
@@ -0,0 +1,153 @@
+#pragma once
+
+#include <map>
+#include <set>
+
+template <typename Key, typename Value>
+class Graph
+{
+  std::map<Key, std::map<Key, Value>> graph;
+
+  // Data based on the graph
+  std::set<Key> nodes;
+
+public:
+  Graph() = default;
+
+  void AddNode(const Key& from)
+  {
+    graph.emplace(from);
+  }
+
+  void AddOneWayEdge(const Key& from, const Key& to, const Value& value)
+  {
+    graph[from][to] = value;
+    nodes.emplace(from);
+  }
+
+  void AddTwoWayEdge(const Key& from, const Key& to, const Value& value)
+  {
+    graph[from][to] = value;
+    graph[to][from] = value;
+    nodes.emplace(from);
+    nodes.emplace(to);
+  }
+
+  Value DFSLong(const Key& from, const Key& to)
+  {
+    std::set<Key> visited;
+    return DFSLong(to, visited, from, Value{});
+  }
+
+  Value DFS(const Key& from, const Key& to)
+  {
+    std::set<Key> visited;
+    return DFS(to, visited, from, Value{});
+  }
+
+  Value Dijkstras(const Key& from, const Key& to) const
+  {
+    std::map<Key, Value> visited;
+    std::multimap<Value, Key> openSet;
+    openSet.emplace(Value{}, from);
+    while (!openSet.empty())
+    {
+      const auto& [cost, node] = *openSet.begin();
+
+      if (node == to)
+        return cost;
+
+      for (auto& [next, nextCost] : graph.find(node)->second)
+      {
+        auto it = visited.find(next);
+        if (it == visited.end() || it->second > cost + nextCost)
+        {
+          openSet.emplace(cost + nextCost, next);
+          visited[next] = cost + nextCost;
+        }
+      }
+      openSet.erase(openSet.begin());
+    }
+    return Value{};
+  }
+
+  std::pair<Value, std::vector<Key>> DijkstrasWithPath(const Key& from, const Key& to) const
+  {
+    std::map<Key, Value> visited;
+    std::multimap<Value, std::vector<Key>> openSet;
+    openSet.emplace(Value{}, std::vector<Key>{from});
+    while (!openSet.empty())
+    {
+      const auto& [cost, path] = *openSet.begin();
+
+      if (path.back() == to)
+        return {cost, path};
+
+      for (auto& [next, nextCost] : graph.find(path.back())->second)
+      {
+        auto it = visited.find(next);
+        if (it == visited.end() || it->second > cost + nextCost)
+        {
+          std::vector<Key> newPath = path;
+          newPath.emplace_back(next);
+          openSet.emplace(cost + nextCost, newPath);
+          visited[next] = cost + nextCost;
+        }
+      }
+      openSet.erase(openSet.begin());
+    }
+    return {Value{}, {}};
+  }
+
+  const Value& GetEdge(const Key& from, const Key& to) const
+  {
+    // Verification that the nodes exists in the graph?
+    return graph.find(from)->second.find(to)->second;
+  }
+
+  const std::map<Key, Value>& GetPaths(const Key& from) const
+  {
+    return graph.find(from)->second;
+  }
+
+  const std::set<Key>& GetNodes() const
+  {
+    return nodes;
+  }
+
+private:
+  Value DFSLong(const Key& to, std::set<Key>& visited, const Key& current, const Value& cost)
+  {
+    if (visited.count(current))
+      return Value{};
+    if (current == to)
+      return cost;
+
+    visited.emplace(current);
+    Value max{};
+    for (auto& [next, nextCost] : graph.find(current)->second)
+    {
+      max = std::max(max, DFSLong(to, visited, next, cost + nextCost));
+    }
+    visited.erase(current);
+    return max;
+  }
+
+  Value DFS(const Key& to, std::set<Key>& visited, const Key& current, const Value& cost)
+  {
+    if (visited.count(current))
+      return Value{};
+    if (current == to)
+      return cost;
+
+    visited.emplace(current);
+    for (auto& [next, nextCost] : graph.find(current)->second)
+    {
+      Value val = DFS(to, visited, next, cost + nextCost);
+      if (val != Value{})
+        return val;
+    }
+    visited.erase(current);
+    return Value{};
+  }
+};