Problem:
Score : 700 points

Problem Statement

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.

Sample Input 1

aabxyyzz

Sample Output 1

2

The solution is to partition s as aabxyyzz = aab + xyyzz.
Here, aab can be permuted to form a palindrome aba, and xyyzz can be permuted to form a palindrome zyxyz.

Sample Input 2

byebye

Sample Output 2

1

byebye can be permuted to form a palindrome byeeyb.

Sample Input 3

abcdefghijklmnopqrstuvwxyz

Sample Output 3

26

Sample Input 4

abcabcxabcx

Sample Output 4

3

The solution is to partition s as abcabcxabcx = a + b + cabcxabcx.

Solution in Ruby (2.3.3) (judge verdict: Runtime Error)

array=gets.chomp.split("")
array2=[]

def tanaka(aa)
    
    pp=2
    bb=aa.uniq
    i=0
    bb.length.times{
        kk=aa.count(bb[i])
        if kk%2==1
            pp-=1
        end
        
        i+=1
        
        if pp<=0
            break
        end
        
        
        
    }
    
   if pp==2
       return "g"
       elsif pp==1
       return "k"
   else return "n"
    
end
        
    
    
end


ii=0
jj=1
max=0

loop{
    if tanaka(array[ii..jj])=="g"
    array2<<"g"
    max=jj
    ii=jj+1
    jj=jj+2
    
    
    elsif tanaka(array[ii..jj])=="k"
    array2<<"k"
    max=jj
    ii=jj+1
    jj=jj+2
    
    
    
else jj+=1
end


if jj>=array.length && ii<=array.length-3
 array2<<"k"
  ii=ii+1
   jj=ii+1
end


if jj>=array.length && ii>=array.length-2  && tanaka(array[ii..jj])=="n"
array2<<"k"
array2<<"k"
break
end



if ii>=array.length
break
end
    
 p [ii,jj]
}

p array2
p max
p array2.count("k")