t = int(input())
for _ in range(t):
    l, r = map(int, input().split())
    x = (((l + r) - (l * 2) + 3) // 4) % 2
    if (l + r) % 2 == 1:
        print(x)
    else:
        if (((l + r) - (l * 2)) // 2 + 1) % 2 == 0:
            print(x)
        else:
            print((l + r) ^ x)