#include <iostream>
#include <fstream>
#include <string>
using namespace std;
const string del=".,!?- ";
inline bool find(string s, char c) {
    for(int i = 0; i < s.size(); ++ i)
        if(s[i] == c)
            return 1;
    return 0;
}
int main()
{
    ifstream fin("text.in");
    ofstream fout("text.out");
     int cuv=0,lit=0;
     string text;
    getline(fin, text);
for(int i=1;i<=sizeof(text);i++)
{
    if(isalpha(text[i]))
        lit++;
    else if(find(del,text[i]))
         cuv++;

}
fout<<lit/cuv;
fin.close();
fout.close();

    return 0;
}