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;

int main(int argc, char *argv[]) {
  string s;
  cin >> s;
  map<int, int> mp = {{0, 0}};
  int now = 0, ans = 0;
  for (auto c : s) {
    now ^= (1 << (c - 'a'));
    int x = 1e9;
    if (mp.count(now)) {
      x = mp[now] + 1;
    }
    for (int i = 0; i < 26; i++) {
      int t = (now ^ (1 << i));
      if (mp.count(t)) {
        x = min(x, mp[t] + 1);
      }
    }
    if (mp.count(now)) mp[now] = min(mp[now], x);
    else mp[now] = x;
    ans = x;
  }
  cout << ans << endl;
  return 0;
}
