#include <iostream.h>      /* allow me to use I/O operations             */

int main()                 /* C++ programs always have a main function  */
                           /*   where execution starts                  */
                           /*   It always returns an int.               */
{
  /* insert "int" before "x = 5;"                */
  /*    need to declare variable before using it */
  x = 5;               /* like Scheme's define expression           */
  int y = 8;

  /* change "Y" to "y" -- "Y" is an undefined variable */
  int z = x + Y;

  /* need semicolon after "y" -- semicolon indicates end of each statement */
  z = x - y               /* like Scheme's set! expression             */
                           /* note: this throws away the previous value */
                           /*       just computed                       */
  
  cout << "This silly program computes ";
  cout << x;
  cout << " minus ";
  cout << y;
  cout << ", equals ";
  cout << z;
  cout << ".\n";

  return 0;               /* return error code 0, i.e., no error       */
/* need closing brace to end program */