#include <fstream>
using namespace std;
ifstream fin ("text.in");
ofstream fout ("text.out");
int cuvinte, litere;
char x,y;
int main () {
	
	while (1) {
		x = fin.get();
		if (x == -1)
			break;
		if ((x>='a' && x<='z') || (x>='A' && x<='Z'))
			litere++;
		else 
			if ((y>='a' && y<='z') || (y>='A' && y<='Z'))
				cuvinte++;
		y=x;
	} 
	
	fout<<litere/cuvinte<<"\n";
	
	
	
	return 0;
}