import sys
input = sys.stdin.readline

T = int(input())
for _ in range(T):
    x, y = map(int, input().split())
    if (x >> y) & 1 == 0:
        print(0)
        continue
    while True:
        if (x >> y) & 1:
            y += 1
        else:
            break
    print(2 ** y - 1)