Rearranging Characters for a Palindrome

You are given a string s. Your task is to determine whether its characters can be rearranged in such a way that the resulting string is a palindrome.

A palindrome is a string that reads the same forwards and backwards. For a string to be able to form a palindrome, the following condition must hold:

$$\text{number of characters with odd frequency} \le 1$$

In other words, at most one character may appear an odd number of times, while all other characters must appear an even number of times.

inputFormat

The input consists of a single line containing the string s.

You should read the input from stdin.

outputFormat

Output a single line to stdout containing either YES if the string can be rearranged to form a palindrome, or NO otherwise.

civic

YES