#include <fstream>
#include <iostream>
#include <string>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");
int i,maxi,n,rasp,x,y,now,nrlit,nrcuv;
string s;

int main()
{
    while (f>>s)
    for (i=0,++nrcuv;i<s.size();++i)
    if (s[i]>='A'&&s[i]<='z')
    nrlit++;
    else
    {
        for (;s[i]<='A'&&s[i]>='z'&&i<s.size();++i);
    }
    g<<nrlit/nrcuv;

    return 0;
}