#include <fstream>
using namespace std;

int main(){
ifstream fin("text.in");
fin>>noskipws;
ofstream fout("text.out");
int nc,nl;
char ca,cc;
nc=nl=0;
fin>>ca;
do{
  fin>>cc;
  if(ca>='a'&&ca<='z' || ca>='A'&&ca<='Z') {
    nl++;
    if(!(cc>='a'&&cc<='z' || cc>='A'&&cc<='Z')) nc++;
    }
  ca=cc;
}while(!fin.eof());
fout<<nl/nc;
fout.close();
return 0;
}