#include<stdio.h>

#include<string.h>

#include<algorithm>

using namespace std;

const int N = ;

int main()

{

    int ans=;

    char s[N];

    while(gets(s))

    {

        for(int i=; s[i]; i++)

        {

            if(s[i]>='A' && s[i]<='Z')

                s[i]+=;

        }

        int pos=;

        while(strstr(s+pos, "doge")!=NULL)

        {

            ans ++;

            pos = strstr(s+pos,"doge")-s+;

        }

    }

    printf("%d\n", ans);

    return ;

}