#include <iostream>
#include <fstream>
using namespace std;
int main ()
{
	char x[10000];
	int i,numar=0,numar2=0;
	ifstream f("text.in");
	f.get(x,100);
	for(i=0;x[i];i++)
		if((x[i]>='a'&&x[i]<='z')||(x[i]>='A'&&x[i]<='Z'))
			numar++;
	for(i=0;x[i];i++)
		if(x[i]==' '||x[i]=='-') numar2++;
	if(x[0]=='-') numar2--;
	ofstream g("text.out");
	g<<numar/numar2;
	g.close();
	f.close();
	return 0;
}