#include <cstdio>
#include <cstring>
#include <algorithm>

#define rep(i, n) for(int i = 0; i < (n); ++i)

using namespace std;

int n;
char s[101];

int main(){
	scanf("%s", s);
	n = strlen(s);
	
	printf("%d\n", (int)count(s, s + n, 'm'));
	return 0;
}