#include<fstream.h>
#include<string.h>
int main(){
char a[65535];
unsigned int s=0,k=0,i,y=0;
ifstream f("text.in");
ofstream g("text.out");
while(!f.eof())
	       {
	       f>>a;
	       for(i=0;i<strlen(a);i++)
		{
		if(a[i]>='a'&&a[i]<='z')||(a[i]>='A'&&a[i]<='Z')
			{ while(a[i]>='a'&&a[i]<='z')||(a[i]>='A'&&a[i]<='Z' )
			       {k++;i++;}
			  y++;s+=k;
			}
		k=0;
		}

		}


g<<(int)s/y;
return 0;
}