add graph class methods: GetEdgeIter, SetEdgeWeight

Author: UmbrellaLeaf5

lib/src/graph/graph.hpp

@@ -277,6 +277,16 @@ class Graph {
    */
   weight_t GetEdgeWeight(const std::pair<vert_t, vert_t>& edge) const;
 
+  /**
+   * @brief Меняет вес ребра в взвешенном графе
+   * @param edge: ребро
+   * @param new_weight: вес
+   * @throw `std::logic_error("SetEdgeWeight: graph is not weighted.")`
+   * @throw `std::invalid_argument("SetEdgeWeight: there is no such edge:")`
+   */
+  void SetEdgeWeight(const std::pair<vert_t, vert_t>& edge,
+                     weight_t new_weight);
+
   void AddVert(vert_t vert);
 
   /// @throw `std::invalid_argument(std::string("AddEdge: ") + ex.what())`
@@ -323,6 +333,8 @@ class Graph {
 
     weight_t Weight() const { return weight_; }
 
+    void SetWeight(weight_t new_weight) { weight_ = new_weight; }
+
     // friend Graph;
 
     bool operator==(const Edge& rhs) const {
@@ -359,6 +371,43 @@ class Graph {
 
   static std::pair<vert_t, vert_t> ParseEdgeString_(
       const std::string& edge_str);
+
+  auto GetEdgeIter(const std::pair<vert_t, vert_t>& edge) const {
+    auto [start_vert, end_vert] = edge;
+
+    return std::find_if(
+        edges_.begin(), edges_.end(),
+        [start_vert, end_vert, this](const auto& e) {
+          return (e.StartVert() == start_vert && e.EndVert() == end_vert) ||
+                 (!IsDirected() && e.StartVert() == end_vert &&
+                  e.EndVert() == start_vert);
+        });
+  }
+
+  auto GetEdgeIter(const std::pair<vert_t, vert_t>& edge) {
+    auto [start_vert, end_vert] = edge;
+
+    return std::find_if(
+        edges_.begin(), edges_.end(),
+        [start_vert, end_vert, this](const auto& e) {
+          return (e.StartVert() == start_vert && e.EndVert() == end_vert) ||
+                 (!IsDirected() && e.StartVert() == end_vert &&
+                  e.EndVert() == start_vert);
+        });
+  }
+
+  auto GetEdgeIter(const std::tuple<vert_t, vert_t, weight_t>& edge) const {
+    auto [start_vert, end_vert, weight] = edge;
+
+    return std::find_if(
+        edges_.begin(), edges_.end(),
+        [start_vert, end_vert, weight, this](const auto& e) {
+          return (e.StartVert() == start_vert && e.EndVert() == end_vert &&
+                  e.Weight() == weight) ||
+                 (!IsDirected() && e.StartVert() == end_vert &&
+                  e.EndVert() == start_vert && e.Weight() == weight);
+        });
+  }
 };
 
 template <AllowedVertType vert_t, AllowedWeightType weight_t>

lib/src/graph/graph_methods.cpp

@@ -113,34 +113,13 @@ bool Graph<vert_t, weight_t>::ContainsEdge(
   if (!IsWeighted())
     throw std::logic_error("ContainsEdge: graph is not weighted.");
 
-  auto [start_vert, end_vert, weight] = edge;
-
-  auto it =
-      std::find_if(edges_.begin(), edges_.end(),
-                   [start_vert, end_vert, weight, this](const auto& e) {
-                     return (e.StartVert() == start_vert &&
-                             e.EndVert() == end_vert && e.Weight() == weight) ||
-                            (!IsDirected() && e.StartVert() == end_vert &&
-                             e.EndVert() == start_vert && e.Weight() == weight);
-                   });
-
-  return it != edges_.end();
+  return GetEdgeIter(edge) != edges_.end();
 }
 
 template <AllowedVertType vert_t, AllowedWeightType weight_t>
 bool Graph<vert_t, weight_t>::ContainsEdge(
     const std::pair<vert_t, vert_t>& edge) const {
-  auto [start_vert, end_vert] = edge;
-
-  auto it = std::find_if(
-      edges_.begin(), edges_.end(),
-      [start_vert, end_vert, this](const auto& e) {
-        return (e.StartVert() == start_vert && e.EndVert() == end_vert) ||
-               (!IsDirected() && e.StartVert() == end_vert &&
-                e.EndVert() == start_vert);
-      });
-
-  return it != edges_.end();
+  return GetEdgeIter(edge) != edges_.end();
 }
 
 template <AllowedVertType vert_t, AllowedWeightType weight_t>
@@ -149,15 +128,7 @@ weight_t Graph<vert_t, weight_t>::GetEdgeWeight(
   if (!IsWeighted())
     throw std::logic_error("GetEdgeWeight: graph is not weighted.");
 
-  auto [start_vert, end_vert] = edge;
-
-  auto it = std::find_if(
-      edges_.begin(), edges_.end(),
-      [start_vert, end_vert, this](const auto& e) {
-        return (e.StartVert() == start_vert && e.EndVert() == end_vert) ||
-               (!IsDirected() && e.StartVert() == end_vert &&
-                e.EndVert() == start_vert);
-      });
+  auto it = GetEdgeIter(edge);
 
   if (it == edges_.end())
     throw std::invalid_argument("GetEdgeWeight: there is no such edge: " +
@@ -166,6 +137,21 @@ weight_t Graph<vert_t, weight_t>::GetEdgeWeight(
   return it->Weight();
 }
 
+template <AllowedVertType vert_t, AllowedWeightType weight_t>
+void Graph<vert_t, weight_t>::SetEdgeWeight(
+    const std::pair<vert_t, vert_t>& edge, weight_t new_weight) {
+  if (!IsWeighted())
+    throw std::logic_error("SetEdgeWeight: graph is not weighted.");
+
+  auto it = GetEdgeIter(edge);
+
+  if (it == edges_.end())
+    throw std::invalid_argument("SetEdgeWeight: there is no such edge: " +
+                                Edge(edge).Name());
+
+  it->SetWeight(new_weight);
+}
+
 template <AllowedVertType vert_t, AllowedWeightType weight_t>
 void Graph<vert_t, weight_t>::AddVert(vert_t vert) {
   if (!Contains(verts_, vert)) verts_.push_back(vert);