Add any() and remove_any() to ph.

These functions select the easiest-to-remove element in the heap, which
is either the most recently inserted aux list element or the root.  If
no calls are made to first() or remove_first(), the behavior (and time
complexity) is the same as for a LIFO queue.
This commit is contained in:
Jason Evans
2017-03-03 22:51:21 -08:00
parent e201e24904
commit cc75c35db5
2 changed files with 84 additions and 5 deletions

View File

@@ -198,8 +198,10 @@ struct { \
a_attr void a_prefix##new(a_ph_type *ph); \
a_attr bool a_prefix##empty(a_ph_type *ph); \
a_attr a_type *a_prefix##first(a_ph_type *ph); \
a_attr a_type *a_prefix##any(a_ph_type *ph); \
a_attr void a_prefix##insert(a_ph_type *ph, a_type *phn); \
a_attr a_type *a_prefix##remove_first(a_ph_type *ph); \
a_attr a_type *a_prefix##remove_any(a_ph_type *ph); \
a_attr void a_prefix##remove(a_ph_type *ph, a_type *phn);
/*
@@ -223,6 +225,17 @@ a_prefix##first(a_ph_type *ph) { \
ph_merge_aux(a_type, a_field, ph, a_cmp); \
return ph->ph_root; \
} \
a_attr a_type * \
a_prefix##any(a_ph_type *ph) { \
if (ph->ph_root == NULL) { \
return NULL; \
} \
a_type *aux = phn_next_get(a_type, a_field, ph->ph_root); \
if (aux != NULL) { \
return aux; \
} \
return ph->ph_root; \
} \
a_attr void \
a_prefix##insert(a_ph_type *ph, a_type *phn) { \
memset(&phn->a_field, 0, sizeof(phn(a_type))); \
@@ -266,15 +279,52 @@ a_prefix##remove_first(a_ph_type *ph) { \
\
return ret; \
} \
a_attr a_type * \
a_prefix##remove_any(a_ph_type *ph) { \
/* \
* Remove the most recently inserted aux list element, or the \
* root if the aux list is empty. This has the effect of \
* behaving as a LIFO (and insertion/removal is therefore \
* constant-time) if a_prefix##[remove_]first() are never \
* called. \
*/ \
if (ph->ph_root == NULL) { \
return NULL; \
} \
a_type *ret = phn_next_get(a_type, a_field, ph->ph_root); \
if (ret != NULL) { \
a_type *aux = phn_next_get(a_type, a_field, ret); \
phn_next_set(a_type, a_field, ph->ph_root, aux); \
if (aux != NULL) { \
phn_prev_set(a_type, a_field, aux, \
ph->ph_root); \
} \
return ret; \
} \
ret = ph->ph_root; \
ph_merge_children(a_type, a_field, ph->ph_root, a_cmp, \
ph->ph_root); \
return ret; \
} \
a_attr void \
a_prefix##remove(a_ph_type *ph, a_type *phn) { \
a_type *replace, *parent; \
\
/* \
* We can delete from aux list without merging it, but we need \
* to merge if we are dealing with the root node. \
*/ \
if (ph->ph_root == phn) { \
/* \
* We can delete from aux list without merging it, but \
* we need to merge if we are dealing with the root \
* node and it has children. \
*/ \
if (phn_lchild_get(a_type, a_field, phn) == NULL) { \
ph->ph_root = phn_next_get(a_type, a_field, \
phn); \
if (ph->ph_root != NULL) { \
phn_prev_set(a_type, a_field, \
ph->ph_root, NULL); \
} \
return; \
} \
ph_merge_aux(a_type, a_field, ph, a_cmp); \
if (ph->ph_root == phn) { \
ph_merge_children(a_type, a_field, ph->ph_root, \