#include<fstream>
#include<iostream>
using namespace std;
char a[205][205];

int Verificare(char x)
{
	if((x>='a' && x<='z') || (x>='A' && x<='Z') && x!=0) return 1;
	return 0;
}

int main ()
{
	char s[20000];
	int i,k,j,contor=0,nrlit;
	
	ifstream fin ("text.in");
	fin.getline(s,20000);
	fin.close();
	
	k=0;j=0;
	for(i=0;s[i]!=0;i++)
	{
		if(Verificare(s[i]) )
		{
			while(Verificare(s[i]))
			{
				nrlit++;
				i++;
			}
			contor++;
		}
	}
	ofstream fout("text.out");
	fout<<nrlit/contor;
	return 0;
}