import sys, math
sys.setrecursionlimit(1000000)
INF = 1 << 100
#mod = 1000000007
mod = 998244353
input = lambda: sys.stdin.readline().rstrip()
li = lambda: list(map(int, input().split()))

T = int(input())

out = []
for _ in range(T):
    X = input()
    Y = input()
    N, M = len(X), len(Y)
    A = max(N, M)
    ans = 'X' if N > M else 'Y'
    for i in range(A * 3):
        if X[i%N] > Y[i%M]:
            ans = 'X'
            break
        elif X[i%N] < Y[i%M]:
            ans = 'Y'
            break
    out.append(ans)
print(*out, sep='\n')