// text.in.cpp : Defines the entry point for the console application.
//
#include<fstream>
using namespace std;

ifstream fin("text.in");
ofstream fout("text.out");
int main()
{
	char sir[256];
	int sum=0, k=0,cuv=0, i;
	fin.get(sir, 255);
	for (i = 0; sir[i]; i++)
	{
		if (('a' <= sir[i] && sir[i] <= 'z') || ('A' <= sir[i] && sir[i] <= 'Z'))
			k++;
		else 
		{
			if (k)
				cuv++;
			sum += k;
			k = 0;
		}
	}
	if (!cuv)fout << 0;
	else fout << sum / cuv;
	return 0;
}