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;
typedef long long ll;

int cnt[1<<26];

signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << fixed << setprecision(20);
    
    string s;
    cin>>s;
    int n = s.size();
    int INF = 1e9;
    for(int i=0;i<(1<<26);i++) cnt[i] = INF;
    cnt[0] = 0;
    int now = 0;
    int ans;
    for(int i=0;i<n;i++){
        now ^= (1<<(s[i]-'a'));
        int ret = 1e9;
        for(int j=0;j<26;j++){
            ret = min(ret,cnt[now^(1<<j)]+1);
        }
        cnt[now] = min(cnt[now],ret);
        ans = cnt[now];
        //cerr << i << " " << ans << endl;
    }
    ans = max(ans,1);
    cout << ans << endl;
}