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<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int N=2e5+10;
int f[1<<26],d[N];
char s[N];
int main(){
	memset(f,0x3f,sizeof f);
	scanf("%s",s);
	int ns=0,t;f[ns]=0;
	for (int i=0;s[i];++i){
		ns^=1<<(s[i]-'a');
		t=f[ns]+1;
		for (int j=0;j<26;++j) t=min(t,f[ns^(1<<j)]+1);
		f[ns]=min(f[ns],t);
	}
	printf("%d",t);
	return 0;
}