Beautiful String Check

In this problem, you are given a string s consisting of lowercase English letters. Your task is to determine whether it is possible to rearrange the characters of s so that every character appears exactly twice. A beautiful string is defined as follows: $$\text{Every character in the string appears exactly twice}.$$

For example, if s = aabb, since both 'a' and 'b' appear exactly twice, the output should be YES.

inputFormat

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

outputFormat

Output a single line containing YES if it is possible to rearrange the string into a beautiful string (i.e., every character appears exactly twice), otherwise output NO.## sample

aabb

YES