#include <stdio.h>
#include <ctype.h>
#include <iomanip.h>

int main ()
{
  char c;
  freopen("text.in", "r", stdin);
  freopen("text.out", "w", stdout);
  long nrc=0, nrlit=0;
  cin>>resetiosflags(ios::skipws);
  cin>>c;
  while(!cin.eof())
  {
    while(isalpha(c)&&cin>>c)
	nrlit++;
    while(cin>>c&&!isalpha(c));
    nrc++;
  }
  printf("%ld", nrlit/nrc);
  return 0;
}