#include<fstream>
#include<string.h>
using namespace std;
ifstream in("text.in");
ofstream out("text.out");

int main()
{
	char lit;
	int nlit = 0, ncuv = 0, trig = 0;

	while (!(in.eof()))
	{
		in.get(lit);
		if ((lit >= 'A'&& lit <= 'Z') || (lit >= 'a'&& lit <= 'z'))
		{
			nlit++;
			trig = 1;
		}
		else
		{
			if (trig == 1)
				ncuv++;
			trig = 0;
		}
	}
	out << nlit / ncuv;
}