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>
using namespace std;
const int MAXN = 200005;
char str[MAXN];
int num[1<<26];
int dp[MAXN];
int sum;
int main()
{
    scanf("%s", str);
    memset(num, 0x3f, sizeof(num));
    memset(dp, 0x3f, sizeof(dp));
    num[0]=0;
    sum=0;
    int len=strlen(str);
    for(int i=0;i<len;++i)
    {
        int x=1<<(str[i]-'a');
        sum^=x;
        dp[i]=min(dp[i], num[sum]+1);
        for(int j=0;j<26;++j)
            dp[i]=min(dp[i], num[sum^(1<<j)]+1);
        num[sum]=min(num[sum], dp[i]);
    }
    printf("%d\n", dp[len-1]);
    return 0;
}
