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>
typedef long long LL;
#define SORT(c) sort((c).begin(),(c).end())
 
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
 
using namespace std;
int main(void)
{
  string s;
  cin >> s;
  int m[256];
  REP(i,26) m['a'+i]=(1<<i);
  int tmp=0;
  map<int,int> d;
  d[0]=0;
  for(auto i=s.begin();i!=s.end();++i){
    tmp=(tmp^m[*i]);
    d.count(tmp) ? 0 : d[tmp]=33554432;
    REP(j,26) if(d.count(tmp^(1<<j))) d[tmp]=min(d[tmp],d[tmp^(1<<j)]+1);
  }
  cout << max(1,d[tmp]) << endl;
  return 0;
}