#include<cstdio>

 #include<cstdlib>

 #include<algorithm>

 using namespace std;

 struct arr

 {

     int x,y,z;

 }a[];

 int cas,n;

 bool cmp(arr a,arr b)

 {

    if(a.x==b.x) return a.y>b.y;

     else return a.x<b.x;

 }

 int main()

 {

    freopen("1003.in","r",stdin);

    freopen("1003.out","w",stdout);

    scanf("%d",&cas);

    while(cas--)

    {

       scanf("%d",&n);

       int m=n*;

       for(int i=;i<=m;i++)

       {

         scanf("%d%d",&a[i].x,&a[i].y);

         a[i].z=i;

       }

       sort(a+,a+m+,cmp);

       for(int i=;i<=m;i++)

       {

         printf("%d",a[i].z);

         if(!i%) printf("\n");

          else printf(" ");

       }

    }

    return ;

 }