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=2e5+5;
char str[maxn];
map<int, int>mi;
int get(int x)
{
    if(mi.count(x))
    {
        return mi[x];   
    }
    return maxn;
}
void add(int x, int val)
{
    if(!mi.count(x))
    {
        mi[x]=val;
    }
    else mi[x]=min(mi[x], val);
}
int main()
{
    scanf("%s", str);
    int i, j;
    int dp=0, mask=0;
    for(i=0; str[i]; i++)
    {
        add(mask, dp);    
        mask^=1<<(str[i]-'a');
        dp=get(mask)+1;
        for(j=0; j<26; j++)
        {
            dp=min(dp, get(mask^(1<<j))+1);
        }
    }
    printf("%d\n", dp);

}
