Add contains method for single vertex and hash function for SCCs

include/graph/scc.h

@@ -18,11 +18,14 @@ public:
 
   SCC(Digraph<T> G, T id) : id(id) { normalize(); }
 
-  // Return true if v is part of this SCC
-  bool member(const T& v);
+  // Return true if u is part of this SCC
+  bool contains(const T& u) const;
 
   // Representative vertex of this SCC
-  T id;
+  T id{};
+
+  // 
+  std::unordered_map<T, std::unordered_set<T>> neighboorList;
 
   bool operator==(const SCC& o) const;
 private:
@@ -34,25 +37,32 @@ template<typename T>
 void SCC<T>::normalize() {
   for (const auto& u : this->vertices()) {
     for (const auto& v : this->adjList[u]) {
-      if (!this->adjList.count(v)) {
+      if (!this->contains(v)) {
         this->adjList[u].erase(v);
         this->adjList.erase(v);
+        neighboorList[u].insert(v);
       }
     }
   }
 }
 
 template<typename T>
-bool SCC<T>::member(const T& v) {
-  const auto& V = this->vertices();
-  return std::find(V.begin(), V.end(), v) != V.end();
+bool SCC<T>::contains(const T& u) const {
+  return this->adjList.count(u);
 }
 
 template<typename T>
-bool SCC<T>::operator==(const SCC& o) const{
+bool SCC<T>::operator==(const SCC& o) const {
   return id == o.id;
 }
 
+template<typename T>
+struct HashSCC {
+  std::size_t operator()(const SCC<T>& C) const {
+    return static_cast<std::size_t>(C.id);
+  }
+};
+
 }; // namespace graph
 
 #endif