#include<fstream>
using namespace std;
char v[10000];
int main()
{
	int c=0,i,cl=0,ok,sss,l;
	ifstream in("text.in");
	ofstream out("text.out");
	while (in.getline(v,100,' '))
	{
		sss=0;
		ok=0;
		l=strlen(v);
		for (i=0;i<l;i++)
		{
			if ((v[i]>='a'&&v[i]<='z')||(v[i]>='A'&&v[i]<='Z'))
			{
				sss=1;
				if (ok==1)
				{
					c++;
					ok=0;
				}
				cl++;
			}
			else
				ok=1;
		}
		if (sss==1)
			c++;
	}
	out<<cl/c;
	in.close();
	out.close();
	return 0;
}