#include <iostream>
#include <fstream>
#include <string>
using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");
string s,p=" ,.!?-";
int n,i,S=0,k=0;
int main()
{
    getline(fin,s);
    n=s.length()-1;
    for(i=0;i<=n;i++)
    {
        if((s[i]>='A'&&s[i]<='Z')||(s[i]>='a'&&s[i]<='z'))S++;
        if((s[i-1]>='a'&&s[i-1]<='z')&&p.find(s[i])<=6)k++;
    }
    fout<<S/k;
}