#include<fstream>
#include<string>
using namespace std;
char cuvant;
long i,nrlit,nrc,rez;
int main()
{
	ifstream in("text.in");
	ofstream out("text.out");
	while(in.get(cuvant))
	{
		if (( cuvant-'a'>=0 && cuvant-'a'<26 ) || ( cuvant-'A'>=0 && cuvant-'A'<26 ) )
		{
			nrc++;
			while((( cuvant-'a'>=0 && cuvant-'a'<26 ) || ( cuvant-'A'>=0 && cuvant-'A'<26 ) ) )
			{
				nrlit++;
				i++;
				in.get(cuvant);
			}
		}		
	}	
	if ( nrc !=0 )
		rez=nrlit/nrc;
	out<<rez<<"\n";
	

	return 0;
}