#include<fstream>
#include<algorithm>
using namespace std;
ifstream in("lazy.in");
ofstream out("lazy.out");
int arbore[200005];
pair< pair<long long,long long> , pair<int, pair<int,int> > > muchii[200005];
int find_root( int nod ){
    if( arbore[nod] < 0 ){
        return nod;
    }
    else{
        return find_root( arbore[nod] );
    }
}
int n,m,a,b,root_one, root_two, knot_one, knot_two;
long long c1,c2;
int main(){
    in >> n >> m;
    for (int i = 1; i <= m; i ++){
        in >> a >> b >> c1 >> c2;
        muchii[i].first.first = c1;
        muchii[i].first.second = c2*-1;
        muchii[i].second.first = a;
        muchii[i].second.second.first = b;
        muchii[i].second.second.second = i;
    }
    sort (muchii+1, muchii+m+1);
    for (int i = 1; i <= n; i ++){
        arbore[i] = -1;
    }
    for (int i = 1; i <= m; i ++){
        knot_one = muchii[i].second.first;
        knot_two = muchii[i].second.second.first;
        root_one = find_root( knot_one );
        root_two = find_root( knot_two );
        if( root_one == root_two ){
            continue;
        }
        else{
            if( arbore[root_one] <= arbore[root_two] ){
                arbore[root_one] += arbore[root_two];
                arbore[root_two] = root_one;
            }
            else{
                arbore[root_two] += arbore[root_one];
                arbore[root_one] = root_two;
            }
            out << muchii[i].second.second.second<<"\n";
        }
    }
    return 0;
}