#include <fstream>
using namespace std;
 string sir;
bool isLitera(char a){
    if (((a>='a') && (a<='z')) || ((a>='A') && (a<='Z'))) return true;
    return false;
}
int main()
{
    int i,l,k,j,lung,t,n;
    ifstream in("text.in");
    ofstream out("text.out");

    getline(in,sir);
    lung = sir.length();
    l=0;
    t=0;
    n=0;

    for (i=0; i<lung; i++){
        if (isLitera(sir[i])){
            j=i;
            while (isLitera(sir[j])) j++;
            t+=j-i;
            n++;
            i=j;
        }

    }
    out << t/n;

    return 0;
}