#include <iostream>
#include <fstream>
#include <cstring>
using namespace std;

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

string s;
int cuv, lit;

int main()
{
    while(getline(fin,s))
    {
        for(int i=0; i<s.size(); i++)
        {
            if(('a'<=s[i]&&s[i]<='z')||('A'<=s[i]&&s[i]<='Z'))
            {
                cuv++;lit++;i++;
                while(('a'<=s[i]&&s[i]<='z')||('A'<=s[i]&&s[i]<='Z'))
                {
                    lit++;i++;
                }
            }
        }
    }
    fout<<lit/cuv;
    return 0;
}