text: #include <stdio.h>
  const int A = 10;
  int a = 20;
  static int b = 30;
  int c;
  int main(void)
  {
   static int a = 40;
   char b[] = "Hello world";
   register int c = 50;
   printf("Hello world %d\n", c);
   return 0;
  }
  