// Example program
#include <iostream>
#include <vector>
using namespace std;

int main(){
    int n, m;
    cin >> n >> m;
    vector<vector<int>> vec(n);
    for(int i = 0;i < m; ++i){
        int a,b;
        cin >> a >> b;
        a--;b--;
        vec[a].push_back(b);
        vec[b].push_back(a);
    }
}