#include<iostream>
#include<fstream>
#include<string.h>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");

int main()
{
    int i=0,k=0,cuv=1;
    char a[256];
    f.get(a,256,'\0');
    while(a[i]!='\0')
    {
        if (a[i]>=65&&a[i]<=90
           ||a[i]>=97&&a[i]<=122) k++;
        if (a[i]==32) cuv++;
        i++;
    }
    g<<k/cuv;
    return 0;
}