# coding:utf-8
import sys
a = list(map(int, input().split('.')))
b = list(map(int, input().split('.')))
for i in range(3):
    if a[i] > b[i]:
        print('YES')
        sys.exit(0)
    if a[i] < b[i]:
        print('NO')
        sys.exit(0)

print('YES')