#!/usr/bin/python
#-*-coding:utf-8 -*-

T=int(raw_input())
i=0
while i<T:
	n=int(raw_input())
	j=0
	li=[]
	while j<n:
		d=raw_input().strip().split()	
		li.append(d)
		j=j+1
	i=i+1
	b=[]
	b=sorted(li,key=lambda a:int(a[1]),reverse=1)
	s=""
	for v in b:
		print v[0]