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;

map<int, int> dp;
char s[200005];
bool vis[26];

int main(){
	scanf("%s", s);
	int l = strlen(s);
	dp[0] = 0;
	for(int i=0;i<l;i++){
		int c = s[i]-'a';
		vis[c] = 1-vis[c];

		int val = 0;
		for(int j=0;j<26;j++) if(vis[j]) val+=(1<<j);

		int ans = i+1;

		for(int j=0;j<26;j++){
			if(dp.count(val^(1<<j))){
				ans = min(ans, dp[val^(1<<j)]+1);
			}
		}
		if(dp.count(val)) ans = min(ans, dp[val]+1), dp[val] = min(dp[val], ans);
		else dp[val] = ans;

		if(i == l-1) printf("%d\n", ans);
	}
}