#include<bits/stdc++.h>

using namespace std;

int words, letters;

char c;

int main()
{
    freopen("text.in", "r", stdin);
    freopen("text.out", "w", stdout);

    while((c = getchar()) != EOF)
    {
        if(isalpha(c))
        {
            words++;
            letters++;

            while((c = getchar()) != EOF)
            {
                if(isalpha(c))
                {
                    letters++;
                }
                else
                {
                    break;
                }
            }
        }

    }

    cout << letters / words;

    return 0;
}