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
INF = 10 ** 9
s = input()
n = len(s)
l = [0] * (n + 1)
for i in range(n):
    l[i + 1] = l[i] ^ (1 << (ord(s[i]) - ord('a')))
dp = dict()
dp[0] = 0
for x in l[1:]:
    if x not in dp:
        dp[x] = INF
    for j in range(26):
        t = x ^ (1 << j)
        if t in dp:
            dp[x] = min(dp[x], dp[t] + 1)
ans = dp[l[-1]]
if ans == 0:
    print(1)
else:
    print(ans)
