Openjudge: judge whether the string is palindrome

describe

Enter a string , Output whether the string is palindrome . Palindrome refers to a string that reads both forward and backward .

Input

Enter as a line of string （ There are no white space characters in the string , The string length does not exceed 100）.

Output

If the string is a palindrome , Output yes; otherwise , Output no.

Instance input

abcdedcba

Instance output

yes

Code

a = input()
if a == a[::-1]:
    print('yes')
else:
    print('no')