#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;

ifstream fin("text.in");
ofstream fout("text.out");

int lit(char x)
{
    if ((x <= 'Z' && x >= 'A') || (x <= 'z' && x >= 'a'))
        return 1;
    return 0;
}

int main()
{
    int x = 0, y = 0, nr = 0;
    char c;
    while (fin.get(c))
    {
        if (lit(c))
        {
            nr++;
            if (nr == 1)
                y++;
        }
        else
        {
            x += nr;
            nr = 0;
        }
    }
    if (y == 0)
        fout << 0 << '\n';
    else
        fout << x / y << '\n';
    return 0;
}