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;
const int maxn = 200000 + 50;
char a[maxn];
int f[maxn], sum[1 << 26];
int main(){
	scanf("%s", a + 1); int n = strlen(a + 1);
	memset(sum, 0x3f, sizeof(sum));
	int g = 0;
	f[0] = 0; sum[0] = 0;
	for (int i = 1; i <= n; ++i){
		int x = 1 << (a[i] - 'a');
		g ^= x;
		f[i] = sum[g];
		for (int j = 0; j < 26; ++j) f[i] = min(sum[g ^ (1 << j)], f[i]);
		++ f[i];
		sum[g] = min(sum[g], f[i]);
	}
	cout << f[n] << endl;
	return 0;
}