def exam(x): if list1[1] < 16: list1[0] = list1[0] - 10 if list1[0] <= 0: print(0) else: print(list1[0]) elif list1[1] >=20: list1[0] = list1[0] - list1[1] - 20 if list1[0] == 0: print(0) else: print(list1[0]) else: print(list1[0]) a = int(input()) for i in range(a): list1 = list(map(int,input().split())) exam(list1)