import java.util.Scanner;

public class TaskJ {
    public static void main(String[] args) {
        Scanner cin = new Scanner(System.in);
        String s = cin.next();
        int ans = 0;
        for (int i = 0; i < s.length(); ++i) {
            if (s.charAt(i) == 'm') ans++;
        }
        System.out.println(ans);
    }
}