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 std::min;

const int MAXN=2e5+5;

int n;char s[MAXN];
int a[MAXN],f[MAXN],minv[1<<26];

int main()
{
	int i,k;
	scanf("%s",s+1);n=strlen(s+1);
	for(i=1;i<=n;i++) a[i]=a[i-1]^(1<<(s[i]-'a'));
	memset(minv,0x3f,sizeof(minv));minv[0]=0;
	for(i=1;i<=n;i++)
	{
		f[i]=minv[a[i]]+1;
		for(k=0;k<26;k++)
			f[i]=min(f[i],minv[a[i]^(1<<k)]+1);
		minv[a[i]]=min(minv[a[i]],f[i]);
	}
	printf("%d\n",f[n]);
	return 0;
}
