#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;

int main()
{
	char aux[100000];
	long int nrCuvinte = 0,totalLungimi = 0;
	
	fstream in ; in.open("text.in");
	while (in.good())
	{
		in >> aux;
		for (int i=0;i<strlen(aux);i++)
			if (isalpha(aux[i]) != 0)
			{
				totalLungimi++;
			}
			else
				if ((i != strlen(aux)-1) || (isalpha(aux[i+1]) != 0))
				nrCuvinte++;
		nrCuvinte++;
	}
	
	ofstream out; out.open("text.out");
	if (nrCuvinte != 0)
		out << (long int) totalLungimi/nrCuvinte;
	else
		out << totalLungimi;
	out.close();
	
	return 0;
}