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 <iostream>
#include <fstream>
#include <map>
using namespace std;
map<int,int> m;
string s;
int msk,bst,x,j,i,t;
int main()
{
    cin>>s;
    for(i=0;i<s.size();i++)
    {
        x=s[i]-'a';
        msk^=(1<<x);bst=(1<<30);
        for(j=0;j<26;j++)
        {
            t=(msk^(1<<j));
            if(m[t]||t==0)
                bst=min(bst,m[t]+1);
        }
        t=msk;
        if(m[t]||t==0)
            bst=min(bst,m[t]+1);
        m[msk]=min(bst,m[msk]);
        if((!m[msk])&&msk!=0)
            m[msk]=bst;
    }
    cout<<bst;
    return 0;
}
