mod = 998244353


def main():
    import sys
    input = sys.stdin.readline

    for _ in range(int(input())):
        L, R = map(int, input().split())

        X = 2 * L
        Y = L + R
        if (Y - X + 1) % 4 == 0:
            if (Y - X + 1) % 8 == 0:
                print(0)
            else:
                print(1)
        elif (Y - X + 1) % 4 == 1:
            if (Y - X) % 8 == 0:
                print(L + R)
            else:
                print((L + R) ^ 1)
        elif (Y - X + 1) % 4 == 2:
            if (Y - X - 1) % 8 == 0:
                print(1)
            else:
                print(0)
        else:
            if (Y - X - 2) % 8 == 0:
                print(1)
            else:
                print(0)


if __name__ == '__main__':
    main()