Method addEdge

Gfg/Java/implement dfs.java:27–30

(int v, int w)

	// Function to add an edge into the graph
	void addEdge(int v, int w)
	{
		adj[v].add(w); // Add w to v's list.
	}

	// A function used by DFS
	void DFSUtil(int v, boolean visited[])