t=int(input())
while t>0:
    n=int(input())
    a=[['0',0]for i in range(n)]
    for i in range(n):
        tmp=input().split()
        a[i][0]=tmp[0]
        a[i][1]=int(tmp[1])
    a.sort(key=lambda a:(-a[1]))
    for i in range(n):
        print(a[i][0])
    t=t-1