#include <algorithm>
#include <iostream>
#include <cstring>
#include <cstdio>
#include <string>
#include <vector>

#define DEBUG(x) std::cerr << #x << " = " << x << std::endl;
#define forall(G, i_) for (int i_ = 0, __for_siz__ = (int) G.size(); i_ < __for_siz__; ++i_)
#define ALL(x) (x).begin(), (x).end()
typedef long long int lli;
using std::cin;
using std::cout;
using std::endl;

inline int read() {
    int s = 0, x = 1; char ch = getchar();
    while (!isdigit(ch)) { if (ch == '-') x = -x; ch = getchar(); }
    while (isdigit(ch)) { s = s * 10 + ch - '0'; ch = getchar(); }
    return s * x;
}

inline int readll() {
    long long int s = 0, x = 1; char ch = getchar();
    while (!isdigit(ch)) { if (ch == '-') x = -x; ch = getchar(); }
    while (isdigit(ch)) { s = s * 10ll + ch - '0'; ch = getchar(); }
    return s * x;
}

const int MAXN = 2e5 + 10;
const char *pl = "edgnb";

char res[MAXN];

bool check(int x) {
    for (int i = 0; i < 5; ++i) if (pl[i] != res[x + i]) return false;
    return true;
}

int main() {
    scanf("%s", res);
    int len = strlen(res); int ans = 0;
    for (int i = 0; i < len - 4; ++i) {
        if (check(i)) ++ans;
    } printf("%d\n", ans);
    return 0;
}