Given a string word, count the number of characters that needs to be added to word to make it anadrome - a string which is an anagram of some palindrome.

For example, if word = "tattoo", its possible to add a single letter 'a' to make it an andarome "tattoa", letters can be rearranged to become "aottoa", which is a palindrome.

Other examples:
Input : "abcb"
we can add either 'a' or 'c' to make it anadrome.
Output:1

Input: "abab"
Output :0

Input: "abc"
output: 2