#include <fstream>
#include <iostream>
using namespace std;
fstream f("text.in", ios::in);
fstream g("text.out", ios::out);

char c,lastch;
int nr=0,nrl=0;

int e_litera(char c)
{
    if((c>='a' && c<='z') || (c>='A' && c<='Z'))
        return 1;
    return 0;
}
void citire()
{
    f>>noskipws>>c;
    lastch = c;
    nrl+= e_litera(c);
    while(!f.eof())
    {
        f>>c;
        nrl+= e_litera(c);
        if(e_litera(lastch) && !e_litera(c))
            nr++;
        lastch=c;
    }

}
int main()
{
    citire();
    g<<nrl/nr;
    return 0;
}