#include <fstream>
#include <iostream>
#include <string>

using namespace std;

int main()
{
	ifstream f("text.in");
	ofstream g("text.out");
	
	char a;
	int total_len=0,nr=0;
	
	while(!f.eof())
	{
		a=f.get();
		if( (a>='a' && a<='z') || (a>='A' && a<='Z') ) 
		{
			while( (a>='a' && a<='z') || (a>='A' && a<='Z') )
			{
				total_len++;
				a=f.get();
			}
			nr++;
		}
	}
	
	
	g<<total_len/nr;
	
	
	
	
	return 0;
}