#include <iostream>
#include <fstream>

using namespace std;

ofstream g("date.out");
ifstream f("date.in");

char c;
int cuv,lit,q,start;

int main()
{
    start=1;
    do{
        f.get(c);

        if((c>='a' && c<='z') || (c>='A' && c<='Z')){
            lit++;
            if(start){
                cuv++;
                start=0;
            }
        }
        else
            start = 1;

    }while(c != EOF);

    g<<lit/cuv;

    return 0;
}