#include <fstream>
#include <cstring>
using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");
int i,nrlitere,nrcuv;
char sir[500000],*p;
int main()
{
    fin.getline(sir,500000);
    p=strtok(sir," ,!-;.?");
    while(p)
    {
        nrcuv++;
            for(i=0;i<strlen(p);i++)
            nrlitere++;
            p=strtok(NULL," ,!-");
    }
    fout<<nrlitere/nrcuv;
}