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 <cstring>

using namespace std;



int a[200005];
int dp[1 << 26];
const int INF = 1e9;

int main() {
  string s;
  cin >> s;

  for(int i = 0; i < s.size(); i++) {
    a[i+1] = (1 << (s[i] - 'a')) ^ a[i];
    //  cout << a[i+1] << endl;
  }

  for(int i = 0; i < (1 << 26); i++) dp[i] = INF;

  dp[0] = 0;

  int tmp;
  for(int i = 1; i <= s.size(); i++) {
    tmp = dp[a[i]];
    for(int j = 0; j < 26; j++) {
      int s = (1 << j);
      tmp = min(tmp,dp[a[i] ^ s]);
    }
    dp[a[i]] = min(dp[a[i]],tmp + 1);
    //  cout << a[i] <<"   "<<dp[a[i]] << endl;
  }
  cout << tmp + 1 << endl;
}
