Implement Breath First Search (BFS) in a graph in DAA

 Implement Breath First Search (BFS) in a graph in DAA

Program :-

#include <bits/stdc++.h>
using namespace std;
class Graph {
    int V;
    vector<list<int> > adj;
public:
    Graph(int V);
    void addEdge(int v, int w);
    void BFS(int s);
};

Graph::Graph(int V)
{
    this->V = V;
    adj.resize(V);
}
void Graph::addEdge(int v, int w)
{
    adj[v].push_back(w);
}
void Graph::BFS(int s)
{
    vector<bool> visited;
    visited.resize(V, false);
    list<int> queue;
    visited[s] = true;
    queue.push_back(s);
    while (!queue.empty()) {
        s = queue.front();
        cout << s << " ";
        queue.pop_front();
        for (auto adjacent : adj[s]) {
            if (!visited[adjacent]) {
                visited[adjacent] = true;
                queue.push_back(adjacent);
            }
        }
    }
}
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 Breadth First Traversal "
         << "(starting from vertex 2) \n";
    g.BFS(2);
    return 0;
}