#include <fstream>
#include <cstring>
using namespace std;
int main ()
{
	int cv=0,cuv=0,i,n,simb=0;
	char x[1001];
	ifstream f("text.in");
	while ( f.get(x,1000,' ') )
	{
	    simb=0;
        n=strlen(x);
		for(i=0;i<=n;i++)
		{
			if(!((x[i]>='a' && x[i]<='z') || (x[i]>='A' && x[i]<='Z')))
				simb++;
		}
		cv+=n-simb+1;
		if(strlen(x)!=1000)
            cuv++;
		f.get();
	}
		ofstream g("text.out");
		if(!cv)
			cv++;
		g<<cv/cuv;
	return 0;
}