java-algorithms/BreadthFirstSearch.java at main · rishitydv/java-algorithms · GitHub

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importjava.io.*;
importjava.util.*;

classGraph
{
privateintV;
privateLinkedList<Integer> adj[];

Graph(intv)
 {
V = v;
adj = newLinkedList[v];
for (inti=0; i<v; ++i)
adj[i] = newLinkedList();
 }

voidaddEdge(intv,intw)
 {
adj[v].add(w);
 }

voidBFS(ints)
 {
booleanvisited[] = newboolean[V];

LinkedList<Integer> queue = newLinkedList<Integer>();

visited[s]=true;
queue.add(s);

while (queue.size() != 0)
 {

s = queue.poll();
System.out.print(s+" ");

Iterator<Integer> i = adj[s].listIterator();
while (i.hasNext())
 {
intn = i.next();
if (!visited[n])
 {
visited[n] = true;
queue.add(n);
 }
 }
 }
 }


publicstaticvoidmain(Stringargs[])
 {
Graphg = newGraph(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);

System.out.println("Breadth First Traversal "+
"(starting from vertex 2)");

g.BFS(2);
 }
}