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>
#define mset(a,b) memset(a,b,sizeof a)
#define mcpy(a,b) memcpy(a,b,sizeof b)
#define lb(x) ((x)&(-(x)))
#define xx first
#define yy second
#define pb push_back
#define mp make_pair
#define pii pair<int,int> 
#define dalao 1000000007
#define inf 0x3f3f3f3f
#define M (1<<26|1)
#define N 200010
using namespace std;
typedef long long ll;
int n,x,t,f[M];
char s[N];
int main(){
	scanf("%s",s),n=strlen(s);
	mset(f,0x3f),f[0]=0;
	for(int i=0;i<n;i++){
		s[i]-='a',x^=1<<s[i];
		t=f[x]+1;
		for(int j=0;j<26;j++)t=min(t,f[x^(1<<j)]+1);
		f[x]=min(f[x],t);
	}
	printf("%d",t);
	return 0;
}