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;
using ll=long long;
#define fr(i,n) for(unsigned i=0;i<(n);++i)
#define Fr(i,n) for(int i=1;i<=(n);++i)
#define ifr(i,n) for(int i=(n)-1;i>=0;--i)
#define iFr(i,n) for(int i=(n);i>0;--i)
template<class T> void chmin(T&x,T y){if(x>y)x=y;}
template<class T> void chmax(T&x,T y){if(x<y)x=y;}

unsigned c,dp[1u<<26u],d[200001],n{};
int main(){
    d[0]=0;
    while((c=getchar_unlocked()-'a')<26) d[n+1]=d[n]^(1u<<c),++n;
    fill(dp,dp+(1u<<26u),500000);
    dp[d[n]]=0;
    ifr(i,n) fr(j,26) chmin(dp[d[i]],dp[d[i]^(1u<<j)]+1);
    printf("%d\n",max(dp[0],1u));
}