#include<iostream>
#include<string>
#include<fstream>
using namespace std;

int main()
{
	std::string text;
	int count_cuv = 0, count_litere=0;

	std::ifstream input("text.in");
	getline(input, text);
	
	for (int i = 0; i < text.length(); i++)
	{
		if ((text[i] >= 'a' && text[i] <= 'z') || (text[i] >= 'A' && text[i] <= 'Z'))
			count_litere++;
		if (text[i] == ' ')
			count_cuv++;
	}
	count_cuv++;

	ofstream outfile;
	outfile.open("text.out");
	
	outfile<<count_litere/count_cuv;

	return 0;
}