#include <bits/stdc++.h>

using namespace std;
ifstream f("text.in");
ofstream g("text.out");
char a;
int nr,s,s1,nr2;
int main()
{
    while(f.get(a))
    {
        if((a >= 'a' && a <= 'z') ||(a >= 'A' && a <= 'Z'))
        {
            nr++;
        }
        else
        {
            if(a!=' ')
                nr2++;

            s=s+nr;
            s1++;
            nr=0;
        }

    }

    nr2--;
    s1=s1-nr2;
    g<<s/s1;
    return 0;
}