// bfs - for unweighted connected graph
package project0;
import java.util.Arrays;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.Queue;
class Graph {
private int v; // total number of vertices
private LinkedList adj[]; // adjacency list
private boolean visited[];
Graph(int v) {
this.v = v;
this.adj = new LinkedList[v];
this.visited = new boolean[v];
for (int i = 0; i < this.v; i++) {
adj[i] = new LinkedList();
}
}
public void addEdge(int u, int v) { // edge from u -> v
this.adj[u].add(v);
}
public void BFS(int source) {
Queue queue = new LinkedList();
queue.add(source);
visited[source] = true;
while (!queue.isEmpty()) {
int currNode = queue.poll();
System.out.print(currNode + " ");
for (int next : this.adj[currNode]) {
if (!visited[next]) {
visited[next] = true;
queue.add(next);
}
}
}
}
public void BFS_end() {
}
}
public class Main {
public static void main(String args[]) {
Graph g = new Graph(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);
g.BFS(0);
}
}