#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;
}

char s[10005];

int main()
{
    int x = 0, y = 0;
    while (fin.getline(s, 1005))
    {
        int n = strlen(s);
        bool k = 0;
        for (int i = 0; s[i]; i++)
        {
            if (lit(s[i]))
            {
                if (i == n - 1)
                    y++;
                k = 1;
                x++;
            }
            else if (k == 1)
            {
                y++;
                k = 0;
            }
        }
    }
    if (y == 0)
        fout << 0 << '\n';
    else
        fout << x / y << '\n';
    return 0;
}