J. JuPaels Palindrome
time limit per test
1 second
memory limit per test
1024 megabytes
input
standard input
output
standard output

In the mystical realm of Spellbound, a powerful wizard named JuPael has discovered a magical string that holds the key to creating powerful incantations. This string is composed of characters from the english alphabet. The wizards aim to find the largest segment of this string that can be rearranged to form a palindrome, a word that reads the same forwards and backwards.

Your task is to assist the wizards by determining the length of the longest contiguous segment of the string that can be rearranged into a palindrome.

Input

The first line contains an integer $$$N$$$ ($$$1 \leq N \leq 10^6$$$), representing the length of the string. The second line contains the string $$$S$$$, composed of lowercase letters from the english alphabet.

Output

Output a single integer representing the length of the largest segment that can be rearranged into a palindrome.

Examples
Input
15
abacabadabacaba
Output
15
Input
5
abcde
Output
1
Input
10
aaaaaaaaaa
Output
10