Peter has lined up hay bales. Some hay bales contain
parasites and he wants to move the infected hay bales to the
back of the sequence, to minimize the chance that the parasites
spread. To sort the haybales, he repeatedly takes out any three
consecutive hay bales and puts them back in sorted order. Your
task is to calculate the minimum number of operations Peter has
to execute to sort the sequence.
Input
The input contains a single string $s$ ($3
\leq s \leq 500$), the sequence of hay bales. Each
character of $s$ is either
‘C’ (for a clean hay bale) or
‘P’ (for an infected one).
Output
The output must contain one integer, the minimum number of
steps Peter has to execute.
Sample Input 1 
Sample Output 1 
CPCC

1

Sample Input 2 
Sample Output 2 
PPPPCCCC

8

Sample Input 3 
Sample Output 3 
CCCCPPPP

0
