#include<cstdio>
#include<algorithm>
using namespace std;

int N,M,i,j,nr;
int x[200002],y[200002],c1[200002],c2[200002],ind[200002],group[200002];

struct comp
{bool operator()(const int &a, const int &b)const
  {if(c1[a]==c1[b])
    return(c2[a]>c2[b]);
   else
    return(c1[a]<c1[b]);}
};

int group_name(int s)
{if(group[s]==s)
   return s;
 group[s]=group_name(group[s]);
 return group[s];  
}

int unite_groups(int a, int b)
{group[group_name(b)]=group_name(a);}

int main()
{freopen("lazy.in","r",stdin);
freopen("lazy.out","w",stdout);
scanf("%d %d",&N,&M);
for(i=1; i<=M; i++)
  {scanf("%d %d %d %d",&x[i],&y[i],&c1[i],&c2[i]);
   ind[i]=i;}
for(i=1; i<=N; i++)
  group[i]=i;   
sort(ind+1,ind+M+1,comp());   
for(i=1; i<=M; i++)
if(nr<N-1)
  {if(group_name(x[ind[i]])!=group_name(y[ind[i]]))
    {unite_groups(x[ind[i]],y[ind[i]]);
    nr++;
    printf("%d\n",ind[i]);}   
   }
else
  break;
return 0;}