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<iostream>
using namespace std;
char s[200010];
int t[200010];
int f[200010];
int minn[(1<<26)+1];
int main()
{
	scanf("%s",s+1);
	for (int i=1;i<=strlen(s+1);i++)
		t[i]=t[i-1],t[i]^=(1<<(s[i]-'a'));
	for (int i=0;i<=(1<<26)-1;i++) minn[i]=1e9;
	minn[0]=0;
	for (int i=1;i<=strlen(s+1);i++)
	{
		//cout<<"t[i]="<<t[i]<<endl;
		f[i]=1e9;
		for (int j=0;j<=25;j++)
			f[i]=min(f[i],minn[t[i]^(1<<j)]+1);//,cout<<(t[i]^(1<<j))<<" "<<minn[t[i]^(1<<j)]<<endl;
		f[i]=min(f[i],minn[t[i]]+1);
		minn[t[i]]=min(minn[t[i]],f[i]);
	}
	printf("%d",f[strlen(s+1)]);
}