#include <bits/stdc++.h>
#define int long long

using namespace std;

inline int read () {
    int w = 1, s = 0; char ch = getchar ();
    for (; ! isdigit (ch); ch = getchar ()) if (ch == '-') w = -1;
    for (; isdigit (ch); ch = getchar ()) s = (s << 1) + (s << 3) + (ch ^ 48);
    return s * w;
}

const string str = "edgnb";

void solve () {
	string s;
    cin >> s;

    int ans = 0;
    for (int i = 0; i <= s.size () - 5; i ++) {
        if (s.substr (i, 5) == str) {
            ans ++;
        }
    }

    cout << ans << '\n';
} 

signed main () {
	ios::sync_with_stdio (false);
    cin.tie (nullptr);
    
	int T = 1; 
	// cin >> T;
	// T = read ();

	while (T --) {
		solve ();
	}
	
	return 0;
}