//#include <atcoder/all>
#include <bits/stdc++.h>
#include <cmath>
using namespace std;
//using namespace atcoder;
using ll = long long;
#define all(A) A.begin(),A.end()
using vll = vector<ll>;
#define rep(i, n) for (long long i = 0; i < (long long)(n); i++)
using Graph = vector<vector<ll>>;
Graph G;
vll E;
vector<bool> seen;

int main() {
	string S;
	cin>>S;
	ll an=0;
	rep(i,S.size()){
		an+=(S[i]=='m');
	}
	cout<<an<<endl;
	
}