t=int(input())
for j in range(t):
	n=int(input())
	li=[[0 for i in range(2)] for i in range(n)]
	for i in range(n):
		li[i]=map(str,raw_input().strip().split())
		li[i][1]=int(li[i][1])
	li.sort(lambda a,b:b[1]-a[1])
	for x in li:
		print x[0]