#include <fstream>
using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");
int nrlit,nrcuv;
char c,uc;
int main()
{
    while(fin>>c)
    {
        if((c>='A'&&c<='Z')||(c>='a'&&c<='z')) nrlit++;
        if(((uc>='A'&&uc<='Z')||(uc>='a'&&uc<='z')||uc==',')&&(c==' '||c=='-'))nrcuv++;
        uc=c;
    }
    fout<<nrlit/nrcuv;
    return 0;
}