#include <bits/stdc++.h>

using namespace std;

string sir;
ifstream in("text.in");
ofstream out("text.out");

int main()
{
    getline(in, sir);
    sir.push_back('.');

    int nr=0,sum=0,cuv=0;
    for(int i=0;i<sir.size();i++)
        if(isalpha(sir[i]))
            cuv++;
        else if(cuv>0)
            nr++, sum+=cuv, cuv=0;

    out<<sum/nr;
    return 0;
}