CMSC--202 , Section Computer Science II for Majors
Fall 1997 23 September 1997 Solutions to Pointer Exercises

1. 

2. 

3. 

4. typedef int *int_ptr;
   typedef int_ptr arr_type[4];
   
   arr_type foo;
   
   foo[0] = (int_ptr) malloc(sizeof(int));
   *foo[0] = 17;
   foo[1] = NULL;
   foo[2] = foo[0];
   foo[3] = (int_ptr) malloc(sizeof(int));
   *foo[3] = 42;
   

5. typedef char * char_ptr;
   typedef char_ptr cp_array[3];
   
   cp_array * foo;
   
   foo = (cp_array *) malloc(sizeof(cp_array));
   (*foo)[0] = (char_ptr) malloc(sizeof(char));
   *(*foo)[0] = 'A';
   (*foo)[1] = NULL;
   

6. typedef int *int_ptr;
   typedef struct 
      {
        int field1;
        int_ptr field2;
      } blatz_struct;
   typedef blatz_struct *blatz_struct_ptr;
   
   blatz_struct_ptr blatz;
   int_ptr binkle;
   
   binkle = (int_ptr) malloc(sizeof(int));
   *binkle = 16;
   blatz = (blatz_struct_ptr) malloc(sizeof(blatz_struct));
   blatz->field1 = 16;
   blatz->field2 = binkle;
   

7. typedef int *int_ptr;
   typedef int_ptr *int_ptr_ptr;
   typedef struct 
     {
      int_ptr_ptr field1;
      int_ptr_ptr field2;
     } zot_struct;
   
   zot_struct zot;
   
   zot.field1 = (int_ptr_ptr) malloc(sizeof(int_ptr));
   *zot.field1 = (int_ptr) malloc(sizeof(int));
   **zot.field1 = 5;
   zot.field2 = (int_ptr_ptr) malloc(sizeof(int_ptr));
   *zot.field2 = *zot.field1;
   

8. typedef int int_array[3];
   typedef int *int_ptr;
   typedef int_ptr ptr_array[3];
   
   ptr_array glumph;
   int_array blumph;
   
   glumph[0] = blumph;
   glumph[1] = NULL;
   glumph[2] = blumph + 2;
   blumph[1] = 17;