#嘘解法？
T = int(input())
X = []
Y = []
for _ in range(T):
    x = input()*2
    y = input()*2
    lenx = len(x)
    leny = len(y)
    if lenx>leny:
        ceil = -(-lenx//leny)
        y = y*ceil
        y = y[:len(x)]
        if x>=y:
            print('X')
        else:
            print('Y')
    else:
        ceil = -(-leny//lenx)
        x = x*ceil
        x = x[:len(y)]
        if y>=x:
            print('Y')
        else:
            print('X')