BFS.cpp

#include<iostream>
#include<queue>
using namespace std;

void printBFS(int **edges,int n,int sv,bool*visited){
    queue<int>pendingnodes;
    pendingnodes.push(sv);
    visited[sv]=true;
    while(pendingnodes.size()!=0){
        int currentvertex=pendingnodes.front();
        cout<<currentvertex<<" ";
        pendingnodes.pop();
        for(int i=0;i<n;i++){
            if(i==currentvertex){
                continue;
            }
            if(edges[currentvertex][i]==1 && !visited[i]){
                pendingnodes.push(i);
                visited[i]=true;
            }
        }
    }
}
int main(){
    int n,e;    //number of vertex and edges
    cin>>n>>e;
    int **edges=new int *[n];
    for(int i=0;i<n;i++){
        edges[i]=new int[n];
        for(int j=0;j<n;j++){
            edges[i][j]=0;
        }
    }
    for(int i=0;i<e;i++){
        int f,s;
        cin>>f>>s;
        edges[f][s]=1;
        edges[s][f]=1;

    }
    bool*visited=new bool[n];
    for(int i=0;i<n;i++){
        visited[i]=false;
    }
    printBFS(edges,n,0,visited);

    delete[]visited;
    for(int i=0;i<n;i++){
        delete []edges[i];
    }
    delete []edges;
}