Merge pull request AllAlgorithms#11 from underscoreorcus/master

abranhe · web-flow · commit fa42d78ee6a3 · 2018-10-01T23:04:20.000-04:00
DFS added under Graphs
diff --git a/graphs/dfs.cpp b/graphs/dfs.cpp
@@ -0,0 +1,58 @@
+#include<iostream> 
+#include<list> 
+using namespace std; 
+  
+// Graph class represents a directed graph 
+// using adjacency list representation 
+class Graph 
+{ 
+    int V;
+    list<int> *adj; 
+    void DFSUtil(int v, bool visited[]); 
+public: 
+    Graph(int V); 
+    void addEdge(int v, int w);  
+    void DFS(int v); 
+}; 
+  
+Graph::Graph(int V) 
+{ 
+    this->V = V; 
+    adj = new list<int>[V]; 
+} 
+  
+void Graph::addEdge(int v, int w) 
+{ 
+    adj[v].push_back(w); // Add w to v’s list. 
+} 
+  
+void Graph::DFSUtil(int v, bool visited[]) 
+{ 
+    visited[v] = true; 
+    cout << v << " "; 
+    list<int>::iterator i; 
+    for (i = adj[v].begin(); i != adj[v].end(); ++i) 
+        if (!visited[*i]) 
+            DFSUtil(*i, visited); 
+} 
+void Graph::DFS(int v) 
+{  
+    bool *visited = new bool[V]; 
+    for (int i = 0; i < V; i++) 
+        visited[i] = false;
+    DFSUtil(v, visited); 
+} 
+  
+int main() 
+{ 
+    Graph g(4); 
+    g.addEdge(0, 1); 
+    g.addEdge(0, 2); 
+    g.addEdge(1, 2); 
+    g.addEdge(2, 0); 
+    g.addEdge(2, 3); 
+    g.addEdge(3, 3); 
+    cout << "Following is Depth First Traversal (starting from vertex 2)\n"; 
+    g.DFS(2); 
+    return 0; 
+}
