globals (x, y, z, k)
  x <- copy 6;
  %rdi <- copy x;
  print_int();
  %rdi <- copy "\n";
  print_string();

  y <- copy 7;
  %rdi <- copy y;
  print_int();
  %rdi <- copy "\n";
  print_string();

  z <- mul y, x;
  %rdi <- copy z;
  print_int();
  %rdi <- copy "\n";
  print_string();

  k <- sub z, x;
  %rdi <- copy k;
  print_int();
  %rdi <- copy "\n";
  print_string();

end