#include <iostream>
#include <vector>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream fin("politie.in");
ofstream fout("politie.out");
int getInt();
/// //////////////////////////////////

#define mmax 500010
#define cout fout
int ind[mmax],dad[250010];
struct
{
    int x,y,cat,per;
} muc[mmax];
int n,m,D,P;

vector<int> ind_res;

void read()
{
    n=getInt();
    m=getInt();
    D=getInt();
    P=getInt();

    for(int i=1; i<=m; ++i)
    {
        muc[i].x=getInt();
        muc[i].y=getInt();
        muc[i].cat=getInt();
        muc[i].per=getInt();
        ind[i]=i;
    }

}

inline int get_dad(int nod)
{
    if(nod!=dad[nod]) dad[nod]=get_dad(dad[nod]);
    return dad[nod];
}

bool cmp_first(int a,int b)
{
    if(muc[a].cat!=muc[b].cat) return muc[a].cat<muc[b].cat;
    return muc[a].per<muc[b].per;
}

bool cmp_res(int a,int b)
{
    return muc[a].per>muc[b].per;
}

int main()
{
    read();

    sort(ind+1,ind+m+1,cmp_first);

    int i;

    for(i=1; i<=n; ++i) dad[i]=i;

    for(i=1; i<=m; ++i)
    {
        if(get_dad(muc[ind[i]].x)!=get_dad(muc[ind[i]].y))
        {
            ind_res.push_back(ind[i]);
            dad[dad[muc[ind[i]].x]]=muc[ind[i]].y;
        }
    }

    sort(ind_res.begin(),ind_res.end(),cmp_res);

    cout<<muc[ind_res[0]].per<<'\n';

    int cnt;
    for(i=1,cnt=1; cnt<P; ++i)
    {
        if(muc[ind_res[i]].per!=muc[ind_res[i-1]].per)
        {
            ++cnt;
            cout<<muc[ind_res[i]].per<<'\n';

        }
    }
}


unsigned const maxb = 666013;
unsigned ptr = maxb - 1;
char buf[maxb];

int getInt()
{
    int rez = 0;
    while(!(buf[ptr] >= '0' && buf[ptr] <= '9'))
    {
        if(++ptr >= maxb)
        {
            fin.read(buf, maxb);
            ptr = 0;
        }
    }
    while((buf[ptr] >= '0' && buf[ptr] <= '9'))
    {
        rez = rez * 10 + buf[ptr] - '0';
        if(++ptr >= maxb)
        {
            fin.read(buf, maxb);
            ptr = 0;
        }
    }
    return rez;
}