e-olymp
Competitions

Programming Principles 1. Week 2. September 9 - 15. PART 2

Five-digit in order

Five-digit number is given. Determine whether all its digits are in ascending order, starting with the leftmost one. For example, in the number 15689 all digits are arranged in ascending order.

Input

One five-digit number.

Output

Print "YES", if all digits in number are arranged in ascending order, and "NO" otherwise.

Time limit 1 second
Memory limit 128 MiB
Input example #1
15689 
Output example #1
YES
Input example #2
12321
Output example #2
NO