abc0 = list(map(int, input().split(".")))
abc1 = list(map(int, input().split(".")))
for i in range(3):
    if abc0[i] < abc1[i]:
        print("NO")
        break
    elif abc0[i] > abc1[i]:
        print("YES")
        break
    else:
        if i == 2:
            print("YES")
            break