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>
using namespace std;
const int ABC=26;
const int maxn=2e5+2;
const int maxm=1<<ABC;
const int INF=0x3f3f3f3f;
int len,bit=0;
char str[maxn];
int dp[maxm];
int change(char ch){return ch-'a';}
void DP(){
	dp[0]=0;
	for (int i=1;i<(1<<ABC);i++) dp[i]=INF;
	for (int i=1;i<=len;i++){
		bit^=(1<<(str[i]-'a'));
		for (int j=0;j<26;j++) dp[bit]=min(dp[bit],dp[bit^(1<<j)]+1);
	}
}
int main(){
	scanf("%s",str+1);
	len=strlen(str+1);
	DP();
	printf("%d",max(1,dp[bit]));
	return 0;
}