def solve(x, y):
    # XならTrue, YならFalseを返す
    flag = False
    if len(x) > len(y):
        flag = True
        x, y = y, x
    lx = len(x)
    ly = len(y)
    for i in range(2 * ly):
        ilx = i % lx
        ily = i % ly
        if x[ilx] > y[ily]:
            return True ^ flag
        elif x[ilx] < y[ily]:
            return False ^ flag

    return flag


T = int(input())
for _ in range(T):
    x = input()
    y = input()
    print("X" if solve(x, y) else "Y")