#include <iostream>
#include <cstring>
#include <fstream>
using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");

int main()
{
    char c;
    int nrc=0,con=0,s=0;
    while(fin.get(c))
    {
        if(isalpha(c)!=0)
            con++;
        else
        {
            if(con)
            {
            nrc++;
            s=s+con;
            con=0;
            }
        }
    }
    fout<<s/nrc;
    return 0;
}