Graph Implementation as Adjacency List
import java.util.*; class Graph_as_adjacencyList { private int V; // Number of vertices private ArrayList[] adj; Graph_as_adjacencyList(int v) { V = v; adj = new ArrayList[v]; for (int i = 0; i < v; ++i) adj[i] = new ArrayList (); } void addEdge(int v, int w) { adj[v].add(w); //Creating an edge. } void showGraph(){ for(int i=0;i "+adj[i].get(j)); } } } class Graph_as_adjacencyList_Demo{ public static void main(String[] args){ Graph_as_adjacencyList g = new Graph_as_adjacencyList(4); g.addEdge(0, 1); g.addEdge(0, 2); g.addEdge(0, 3); g.addEdge(1, 2); g.addEdge(2, 0); g.addEdge(2, 3); g.addEdge(3, 3); g.addEdge(3, 1); g.showGraph(); } }