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 = 200010;
map<int,int> M;
char s[N];
int main(){
	scanf("%s",s+1);
	int n = strlen(s+1);
	int tmp = 0;
	for(int i =1;i<=n;i++){
		tmp^=1<<(s[i]-'a');
	}
	//cout<<tmp<<endl;
	if(tmp==0){
		puts("1");
		return 0;
	}
	tmp = 0;
	M[0] = 0;
	int tmp2,cnt;
	for(int i =1;i<=n;i++){
		tmp^=1<<(s[i]-'a');
		tmp2 = 1e9;
		cnt = 0;
		for(int j = 0;j<26;j++) {
		
			if(M.count(tmp^(1<<j)))
				tmp2 = min(tmp2,M[tmp^(1<<j)]+1);
			if(tmp>>j&1) cnt++;
		}
		if(cnt==1) tmp2 = 1;
		if(M.count(tmp)) M[tmp] = min(M[tmp],tmp2);
		else M[tmp] = tmp2;
	}
	printf("%d\n",M[tmp]);
	return 0;
} 