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>
typedef long long ll;
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,a) FOR(i,0,a)
	
using namespace std;
const int ALP='z'-'a'+1,MAX_N=2e5,INF=1e8;
string S;
int N,opt[MAX_N+1],dp[1<<ALP],cnt[ALP];
int main(){
	cin>>S;
	N=(int)S.size();
	opt[0]=0;
	fill(dp,dp+(1<<ALP),INF);
	dp[0]=0;
	int b=0;
	REP(i,N){
		b^=1<<(S[i]-'a');
		opt[i+1]=dp[b]+1;
		REP(j,ALP){
			opt[i+1]=min(dp[b^(1<<j)]+1,opt[i+1]);
		}
		dp[b]=min(dp[b],opt[i+1]);
	}
	cout<<opt[N]<<endl;
}