#include <bits/stdc++.h>

using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");
bool cuvon;
char ch;
int nrlet,nrcuv;
int main()
{
    while(!fin.eof())
    {
        ch=fin.get();
        if((ch-'0'>=17 && ch-'0'<=42) || (ch-'0'>=49 && ch-'0'<=74))
        {
            nrlet++;
            if(cuvon==0)cuvon=1,nrcuv++;
        }
        else cuvon=0;
    }
    fout << nrlet/nrcuv << '\n';
    return 0;
}