#include <iostream>
#include <string.h>
#define DIM 500000
#include <fstream>
using namespace std;
int main()
{
    ifstream cin ("text.in");
    ofstream cout ("text.out");
    char s;
    int nr1 = 0, nr2 = 0;
    while (cin >> noskipws >> s){
        if (isalpha(s)){
            nr1 ++;
            while (isalpha(s)){
                nr2 ++;
                cin >> noskipws >> s;
            }
        }
    }
    cout << nr2 / nr1 ;
    return 0;
}