Can Form Palindrome?

Given a string \(s\) with length \(1 \leq |s| \leq 100000\), determine if the characters of \(s\) can be rearranged to form a palindrome.

A palindrome is a string that reads the same backward as forward. In order for a rearrangement of \(s\) to form a palindrome, at most one character is allowed to have an odd frequency; all other characters must appear an even number of times.

For example, the string aabb can be rearranged into abba which is a palindrome, whereas abc cannot be rearranged into any palindrome. Your task is to check if the given string can be rearranged to form a palindrome.

inputFormat

The input consists of a single string \(s\) provided via standard input (stdin). The string contains only standard printable characters and may include spaces.

outputFormat

Output a single line to standard output (stdout) containing YES if the string's characters can be rearranged to form a palindrome, or NO otherwise.

aabb

YES