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

ifstream fin("lazy.in");
ofstream fout("lazy.out");

class sets {
private:

    int t[200001];

public:

    sets()
    {
        for (int i = 1; i <= 200000; i++)
            t[i] = i;
    }

    int root(int x)
    {
        if (t[x] == x)
            return x;
        else
            return t[x] = root(t[x]);
    }

    void unit(int x, int y)
    {
        t[root(x)] = root(y);
    }

    bool connected(int x, int y)
    {
        return root(x) == root(y);
    }
};

int n, m;
sets S;

struct edge {
    int x, y, poz, c1, c2;

    bool operator < (edge aux)
    {
        if (c1 < aux.c1)
            return true;
        else if (c1 == aux.c1 && c2 > aux.c2)
            return true;
        return false;
    }

}v[200001];

int main()
{
    fin >> n >> m;

    for (int i = 1; i <= m; i++)
    {
        fin >> v[i].x >> v[i].y >> v[i].c1 >> v[i].c2;
        v[i].poz = i;
    }

    sort(v + 1, v + m + 1);

    for (int i = 1; i <= m; i++)
        if (!S.connected(v[i].x, v[i].y))
            fout << v[i].poz << '\n', S.unit(v[i].x, v[i].y);

    return 0;
}