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 dp[1 << 26];
#define INF (INT_MAX/2)

int main(void)
{
    string s;
    cin >> s;
    int n = s.length();

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

    int b = 0;
    dp[0] = 0;
    for(int i = 0; i < n; i++)
    {
        b ^= (1 << (s[i] - 'a'));
        int t = dp[b];

        for(int j = 0; j < 26; j++)
        {
            t = min(t, dp[b ^ (1 << j)]);
        }
        dp[b] = min(dp[b], t + 1);
    }
    cout << (dp[b] == 0 ? 1 : dp[b]) << "\n";
    return 0;
}
