#include<fstream>
#include<algorithm>
using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");

int main()
{
    char sepc[]=".,!- ;?";
    char p[100], c[2];
    int i,nr=0,lg=0;
    fin>>c;
    while( !fin.eof() )
    {
           fin>>p;
           for(i=0;i<strlen(p);i++) if(p[i] != '!' && p[i] != '.' && p[i] != ',' && p[i] != '?' && p[i] != ';' && p[i] != ';' && p[i] != '-' ) lg++;
           nr++;                                 
           
    }
    fout<<lg/nr;
    fin.close();
    fout.close();
    return 0;
}