#include <fstream>

using namespace std;
ifstream f("text.in");
ofstream g("text.out");
char a;
int i, words, Lung, p, ok;
int main()
{   i = 1;
    while(f.get(a)){
        if(((a >= 'a' && a <= 'z') || (a >= 'A' && a <= 'Z')) && ok == 0){
            p = i;
            ok = 1;
        }
        if(!((a >= 'a' && a <= 'z') || (a >= 'A' && a <= 'Z')) && ok == 1){
            Lung = Lung + i - p;
            ok = 0;
            words++;
        }
        i++;
    }
    g << Lung / words;
    return 0;
}