n1=int(input())
for t1 in range(n1):
    n2=int(input())
    lst1=[]
    for t2 in range(n2):
        a,b = input().split()
        lst1.append([a,int(b)])
    lst1.sort(key= lambda n:-n[1])
    lst2=[i[0] for i in lst1]
    ##print(lst2)
    s="\n".join(lst2)
    print(s)