#include <fstream>
using namespace std;
ifstream cin("text.in");
ofstream cout("text.out");
int main()
{
    int sum=0,nr=0,ac=0;
    char s;
    while(int(s)!=10)
    {
        s=cin.get();
        int x=int{s};
        if(x>=65 and x<=90)
            ac++;
        else
        if(x>=97 and x<=122)
            ac++;
        else
            if(ac>0)
            {
                sum=sum+ac;
                ac=0;
                ++nr;
            }
    }
    cout<<sum/nr;
    cin.close();
    cout.close();
    return 0;
}