#D7864. Palindromic Anagram
Palindromic Anagram
Palindromic Anagram
Problem statement
Given the string . Find the number of all anagrams in that are palindromic.
An anagram of the string is an anagram of , which means that is equal to , or that the rearranged characters of are equal to . For example, for the string abcd, abcd and cbda are anagrams, but abed, cab and abcdd are not anagrams.
When the string is a palindrome, it means that the reverse reading of is equal to itself. For example, abc and ab are not palindromes, and a and abccba are palindromes.
Constraint
- ( is the length of the string )
- contains only lowercase letters.
- The answer is guaranteed to be less than .
input
Input follows the following format.
output
Output the number on one line.
Examples
Input
ab
Output
0
Input
abba
Output
2
inputFormat
input
Input follows the following format.
outputFormat
output
Output the number on one line.
Examples
Input
ab
Output
0
Input
abba
Output
2
样例
ab
0