#include <fstream>
#include <cstring>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");
char a[10000000];
int main()
{
	int i;
	
	int cuvinte=0, litere=0;
	while(!f.eof())
	{
	f.getline(a, 10000000);
	int lim=strlen(a);
	for(i=0; i<lim; i++)
	{
		if((a[i]>=65 && a[i]<=90) || (a[i]>=97 && a[i]<=122))
			litere++;
		else if((a[i+1]>=65 && a[i+1]<=90) || (a[i+1]>=97 && a[i+1]<=122))
			cuvinte++;
	}
	}
	g<<litere/cuvinte;
}