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;

int best[67108864];

int main(){
	string s;
	cin >> s;
	int n = (int)s.length();
	for(int i = 0; i<(1<<26); i++){
		best[i] = n+3;
	}
	best[0] = 0;
	int cur = 0;
	int ans = 0;
	for(int i = 0; i<n; i++){
		cur ^= (1<<((int)(s[i]-'a')));
		ans = best[cur]+1;
		for(int j = 0; j<26; j++){
			best[cur] = min(best[cur],best[cur^(1<<j)]+1);
			ans = min(ans,best[cur^(1<<j)]+1);
		}
	}
	cout << ans << endl;
}