#include<bits/stdc++.h>
using namespace std;
int a[10000001];
int main()
   {
   	int q,n,t;
   	
   	scanf("%d",&t);
   	while(t--)
   	     {
   	       scanf("%d%d",&n,&q);
		   for(i=0;i<n;i++)
		       a[i] = i+1;
			   
		printf("-1\n")    	  	
		 }
   	
   	
   	
   	
   	return 0;
   }