BFSTraversalGraphs.cpp

#include <iostream>
#include <bits/stdc++.h>
using namespace std;


/*BFS Traversal of graph
Breadth First Search
also called level ordeer traversal
*/

class Graph{
    map<int, list<int> > l;
    public:

    void addEdge(int x, int y){
        l[x].push_back(y);
        l[y].push_back(x);
    }

    void bfs(int src){
        queue<int> q;
        map<int, bool> visited;

        q.push(src);
        visited[src]= true;

        while(!q.empty()){
            int node= q.front();
            q.pop();
            cout<< node<< " ";

            for(int nbr: l[node]){
                if(!visited[nbr]){
                    q.push(nbr);
                    visited[nbr]= true;
                }
            }
            
        }
        
    }
};


int main() {
    Graph g;
    g.addEdge(0,1);
    g.addEdge(1,2);
    g.addEdge(2,3);
    g.addEdge(3,4);
    g.addEdge(4,5);

    g.bfs(0);
}