main :: () -> void {
  a :u64= 1;
  b :*u64 = &a;
  print_u64 b.*;
  print_u64 a;
  b.* = 2;
  print_u64 b.*;
  print_u64 a;
  a = 3;
  print_u64 b.*;
  print_u64 a;
};