#define WSIZE       4       /* word size (bytes) */
#define DSIZE       8       /* doubleword size (bytes) */
#define CHUNKSIZE   (1<<12) /* initial heap size (bytes) */
#define OVERHEAD    8       /* overhead of header and footer (bytes) */

#define MAX(x, y)   ((x) > (y) ? (x) : (y))

/* Pack a size and allocated bit into a word */
#define PACK(size, alloc) ((size) | (alloc))

/* Read and write a word at address p */
#define GET(p)      (*(size_t *)(p))
#define PUT(p, val) (*(size_t *)(p) = (val))

/* Read the size and allocated feilds from address p */
#define GET_SIZE(p)     (GET(p) & ~0x7)
#define GET_ALLOC(p)    (GET(p) & 0x1)

/* Given block ptr bp, compute address of its header and footer */
#define HDRP(bp)    ((char *)(bp) - WSIZE)
#define FTRP(bp)    ((char *)(bp) + GET_SIZE(HDRP(bp)) - DSIZE)

/* Given block ptr bp, compute address of next and prev blocks */
#define NEXT_BLKP(bp)   ((char *)(bp) + GET_SIZE(((char *)(bp) - WSIZE)))
#define PREV_BLKP(bp)   ((char *)(bp) - GET_SIZE(((char *)(bp) - DSIZE)))

/* Function prototypes */
int my_init(void);
void my_free(void *bp);
void *my_malloc(size_t size);