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


int main(void)
{
	int length; char * buffer;
	ifstream is("text.in");
	ofstream fout("text.out");
	is.seekg (0, ios::end);
	length = is.tellg();
	is.seekg (0, ios::beg);
	buffer = new char [length];
	is.read (buffer,length);
	is.close();
	int n,i,num=0, cuv=1;
	for(i=0;i<length-1;i++)
	{
		if(buffer[i]>='a' && buffer[i]<='z' || buffer[i]>='A' && buffer[i]<='Z') num++;
		if(buffer[i]==' ') cuv++;
	}
	fout<<num/cuv;
	return 0;
}