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;
#define MAXN    (200020)
#define inf     (0x3fffffff)
typedef priority_queue< int , vector<int> , greater<int> > spq;

int sl;
char s[MAXN];
int f[MAXN];
int dp[MAXN];
int m[67108864];

int main(void)
{
    int i, j;
    scanf("%s", s+1); sl = strlen(s+1);
    for(i = 1;i <= sl;++i)
    {
        f[i] = 1 << (s[i]-'a');
        f[i] ^= f[i-1];
    }
    for(i = 1;i < 67108864;++i) m[i] = inf;
    m[0] = 0;
    for(i = 1;i <= sl;++i)
    {
        int dpi = m[f[i]];
        for(j = 0;j < 26;++j)
            dpi = min(dpi, m[f[i]^(1<<j)]);
        dp[i] = dpi+1;
        m[f[i]] = min(m[f[i]], dp[i]);
    }
    printf("%d\n", dp[sl]);
    return 0;
}
