#include <iostream>
#include<string>
#include<fstream>
#include<algorithm>
using namespace std;
int main(){
	int risultato=0;
    ifstream in;
    ofstream ou;
    in.open("input.txt");
    string a;
    getline(in,a);
    for(int i=0;i<a.length();i++){
    	if(a[i]=='h'&&a[i+1]=='e'&&a[i+2]=='l'&&a[i+3]=='l'&&a[i+4]=='o'){
    		for(int k=i+5;k<a.length();k++){
    			if(a[k]=='w'&&a[k+1]=='o'&&a[k+2]=='r'&&a[k+3]=='l'&&a[k+4]=='d')
    				risultato++;
			}
		}
	}
	ou.open("output.txt");
	ou<<risultato;
    return 0;
}