# coding=utf-8:

lineA = input().split('.')
lineB = input().split('.')

for i, num in enumerate(lineA):
    lineA[i] = int(num)
    
for j, num in enumerate(lineB):
    lineB[j] = int(num)

c = 0
for a, b in zip(lineA, lineB):
    if a < b:
        print("NO")
        break
    elif a > b:
        print("YES")
        break
    else:
        continue