def digit(x: int, i: int) -> int:
    return (x // (10**i)) % 10


def solve(A: int, B: int) -> bool:
    for i in range(10):
        if digit(A, i) < digit(B, i):
            return False
    return True


A, B = map(int, input().split())
print("Yes" if solve(A, B) else "No")