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

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

	std::ifstream input("text.in");
	getline(input, text);
	
	for (unsigned int i = 0; i < text.length(); i++){
		if ((text[i] >= 'a' && text[i] <= 'z') || (text[i] >= 'A' && text[i] <= 'Z'))
			count_litere++;
		else{
			if (i >= 1 && i <= text.length()){
					if (((text[i - 1] >= 'a' && text[i - 1] <= 'z') || (text[i - 1] >= 'A' && text[i - 1] <= 'Z')))
					{
						count_cuv++;
					}

			}
		}
	}

	if ((text[text.length()-1] >= 'a' && text[text.length()-1] <= 'z') || (text[text.length()-1] >= 'A' && text[text.length()-1] <= 'Z'))
		count_cuv++;

	std::ofstream output("text.out");
	if (count_cuv != 0){
		output << count_litere / count_cuv;
	}
	else{
		output << count_litere;
	}

	return 0;
}