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];

int main()
{
	string s;
	cin >> s;
	for (int i = 0; i < (1 << 26); i++) {
		dp[i] = s.size();
	}
	int X = 0;
	dp[0] = 0;
	for (auto c : s) {
		int b = c - 'a';
		X ^= 1 << b;
		int nv = dp[X] + 1;
		for (int i = 0; i < 26; i++) {
			nv = min(nv, dp[X ^ (1 << i)] + 1);
		}
		dp[X] = min(dp[X], nv);
	}
	cout << max(dp[X], 1) << endl;
	return 0;
}
