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

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