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<cstdio>
#include<cstring>
#include<algorithm>
#include<map>
using namespace std;
map<int,int> s;
char w[310001];
int i,j,k,n,f[310001],a[310001];
int main(){
	scanf("%s",w+1);n=strlen(w+1);s.clear();
	for (i=1,a[0]=f[0]=0;i<=n;i++) a[i]=a[i-1]^(1<<(w[i]-'a'));
	s[0]=0;
	for (i=1;i<=n;i++){
		f[i]=n+1;
		if (s.count(a[i])) f[i]=s[a[i]]+1;
		for (j=0;j<26;j++)
		 if (s.count(a[i]^(1<<j))) f[i]=min(f[i],s[a[i]^(1<<j)]+1);
		if (!s.count(a[i])) s[a[i]]=f[i];else s[a[i]]=min(s[a[i]],f[i]);
	}
	printf("%d\n",f[n]);
	return 0;
}