#include <iostream>
#include <fstream>
#include <string>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");
int i,j,k,n,nr;
int main()
{
    string s;
    getline(f,s);
    for(i=0;i<=s.size();i++)
     {
         k++;
        if(s[i]==' ' || s[i]=='!' || s[i]=='.' || s[i]==',' || s[i]=='-')
            n++;
     }
     j=k-n-1;
     for(i=0;i<=s.size();i++)
         if(s[i]==' ' || s[i]=='!' || s[i]=='.' || s[i]==',' || s[i]=='-')
            if(s[i-1]>='a' && s[i-1]<='z')
         nr++;

 g<<j/nr;


    return 0;
}