#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i)

using namespace std;

int main() {
    int n;
    string s;
    cin >> n >> s;
    
    string p = "HAPPY";
    int ans = 0;
    rep(i, n-9) {
        if (s.substr(i, 5) == p)  {
            s[i+2] = '#';
            ++ans;
        }
    }
    rep(i, 5) {
        if (s[n-5+i] != p[i]) ++ans;
    }
    
    cout << ans << '\n';
    
    return 0;
}