We have a string s consisting of lowercase English letters. Snuke is partitioning s into some number of non-empty substrings. Let the subtrings obtained be s_1, s_2, ..., s_N from left to right. (Here, s = s_1 + s_2 + ... + s_N holds.) Snuke wants to satisfy the following condition:

* For each i (1 \leq i \leq N), it is possible to permute the characters in s_i and obtain a palindrome.



Find the minimum possible value of N when the partition satisfies the condition.

Constraints

* 1 \leq |s| \leq 2 \times 10^5
* s consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:


s


Output

Print the minimum possible value of N when the partition satisfies the condition.

Examples

Input

aabxyyzz


Output

2


Input

byebye


Output

1


Input

abcdefghijklmnopqrstuvwxyz


Output

26


Input

abcabcxabcx


Output

3
#include "bits/stdc++.h"
using namespace std;
const int N = 3e5 + 5;
const int M = 1 << 26;
char str[N];
int n;
int bst[M];
int dp[N];
int pre[N];
int main(){
	scanf("%s" , str + 1);
	n = strlen(str + 1);
	for(int i = 0 ; i < M ; ++i){
		bst[i] = N;
	}
	pre[0] = 0;
	for(int i = 1 ; i <= n ; ++i){
		pre[i] = pre[i - 1] ^ (1 << (str[i] - 'a'));
	}
	dp[n + 1] = 0;
	for(int i = n ; i >= 1 ; --i){
		bst[pre[i]] = min(bst[pre[i]] , dp[i + 1]);
		int res = bst[pre[i - 1]];
		for(int j = 0 ; j < 26 ; ++j){
			res = min(res , bst[pre[i - 1] ^ (1 << j)]);
		}
		dp[i] = res + 1;
	}
	printf("%d\n" , dp[1]);
}