Pointers in __crush_do_rule__ function of CRUSH mapper file

Hi all, I have a question regarding pointer variables used in the __crush_do_rule__ function of CRUSH __mapper.c__. Can someone please help me understand the purpose of following four pointer variables inside __crush_do_rule__: int *b = a + result_max; int *c = b + result_max; int *w = a; int *o = b; The function __crush_do_rule__ is below: /** * crush_do_rule - calculate a mapping with the given input and rule * @map: the crush_map * @ruleno: the rule id * @x: hash input * @result: pointer to result vector * @result_max: maximum result size * @weight: weight vector (for map leaves) * @weight_max: size of weight vector * @cwin: Pointer to at least map->working_size bytes of memory or NULL. */ int crush_do_rule(const struct crush_map *map, int ruleno, int x, int *result, int result_max, const __u32 *weight, int weight_max, void *cwin, const struct crush_choose_arg *choose_args) { int result_len; struct crush_work *cw = cwin; int *a = (int *)((char *)cw + map->working_size); int *b = a + result_max; int *c = b + result_max; int *w = a; int *o = b; int recurse_to_leaf; int wsize = 0; int osize; int *tmp; const struct crush_rule *rule; __u32 step; int i, j; int numrep; int out_size; Thanks Bobby !