import java.util.*;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		String s=sc.next();
		sc.close();
		int count=0;
		for(char c : s.toCharArray()){
			if(c=='m'){
				count++;
			}
		}
		System.out.println(count);
		}
	}