Problems
Four-digit palindrom
Four-digit palindrom
Four-digit number is given. Determine is it a palindrome. A positive integer is a palindrome if it is read the same from left to right and from right to left. For example the number $2332$ is palindrome.
\InputFile
Onr four-digit number $n$.
\OutputFile
Print "\textbf{YES}", if the number $n$ is a palindrome, and "\textbf{NO}" otherwise.
Input example #1
2332
Output example #1
YES
Input example #2
5446
Output example #2
NO