Problem - Kevin Tafuro

arrays. This array type will hide the management of the array restructuring from the
programmer.
typedef enum {
SPC_ARRAY_SPLIT, SPC_ARRAY_MERGE, SPC_ARRAY_FOLD, SPC_ARRAY_FLAT
} spc_array_type;
typedef struct {
spc_array_type type;
int sz_elem;
int num_elem;
int split;
unsigned char data[1];
} spc_array_t;
Four functions—spc_array_split( ), spc_array_merge( ), spc_array_fold( ), and spc_
array_flat( )—are provided for creating arrays. The spc_array_get( ) function
retrieves an element from an array, and the spc_array_set( ) function sets an element
in the array. Use spc_array_free( ) to destroy an array.
#include
#include
/* Create a split array of num_elem elements, each of size sz_elem */
spc_array_t *spc_array_split(int sz_elem, int num_elem) {
double size;
spc_array_t *a;
size = (((double)sz_elem * (double)num_elem) / 2) + (double)sizeof(spc_array_t);
if (size > (double)INT_MAX) return 0;
if (!(a = (spc_array_t *)calloc((size_t)size, 1))) return 0;
a->type = SPC_ARRAY_SPLIT;
a->sz_elem = sz_elem;
a->num_elem = num_elem;
a->split = 2; /* array is split into 2 arrays */
return a;
}
/* Create two merged arrays with num_first elements in array 1 and num_second
* elements in array 2
*/
spc_array_t *spc_array_merge(int sz_elem, int num_first, int num_second) {
double size;
spc_array_t *a;
size = (((double)num_first + (double)num_second) * (double)sz_elem) +
(double)sizeof(spc_array_t);
if (!num_first || size > (double)INT_MAX) return 0;
if (!(a = (spc_array_t *)calloc((size_t)size, 1))) return 0;
a->type = SPC_ARRAY_MERGE;
a->sz_elem = sz_elem;
a->num_elem = num_first + num_second;
a->split = num_first / num_second;
if (!a->split) a->split = (num_second / num_first) * -1;
return a;
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Restructuring Arrays | 673