#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");
string sir;
int nr_lit, nr_cuv, len;
bool litera(char x)
{
    return (x >= 'a' && x <= 'z' || x >= 'A' && x <= 'Z');
}
int main()
{
    getline(fin, sir);
    for(int i=1; i<=sir.size(); ++i)
    {
        if(litera(sir[i]))len++;
        else if(len)
        {
            nr_lit += len;
            nr_cuv++;
            len = 0;
        }
    }
    fout << nr_lit / nr_cuv;
}