#include<bits/stdc++.h>
#define LL long long
using namespace std;
const int N=1.1e6;
inline LL read(){
	LL x=0,ff=1;
	char c=getchar();
	while(!isdigit(c)&&c!='-') c=getchar();
	if(c=='-') c=getchar(),ff=-1;
	while(isdigit(c)) x=x*10ll+c-'0',c=getchar();
	return x*ff;
}
int n;
int cnt[N];
char c[N];
int main(){
//	freopen(".in","r",stdin);
//	freopen(".out","w",stdout);
	int casecnt=1;
	while(casecnt--){
		scanf("%s",c+1);
		n=strlen(c+1);
		for(int i=1;i<=n;++i)
			cnt[c[i]-'A']++;
		printf("%d\n",min((cnt['C'-'A']-1)/2,cnt['P'-'A']));
	}
	return 0;
}