Graph construction

#include <bits/stdc++.h>
using namespace std;
int main() {
    int v;
    int e;
    cout<<"Enter vertex and edges \n";
    cin>>v;
	cin>>e;
    vector<vector<int> >graph(v);

    for(int i=0; i<e; i++){
        int a,b;
        cout<<"Enter Two nodes which are connected \n";
        cin>>a;
		cin>>b;
        graph[a].push_back(b);
        graph[b].push_back(a);//Remove this if you want directed
    }

    for(int i = 0; i<v; i++){
        for(int j = 0; j<graph[i].size(); j++){
            cout<<graph[i][j]<<" ";
        }
        cout<<endl;
    }

}