O (nlgk) problem priority queue implementation file C Language

/* Priorityqueue. C -- Minimum heap implementation file */<br/> # include "priorityqueue. H "</P> <p>/* local function declaration */</P> <p> static bool percolateup_p (prioritynode * const heap, const int position, const int size); <br/> static bool percolatedown_p (prioritynode * const heap, const int position, const int size ); </P> <p>/* interface function definition */</P> <p> bool initialize_p (priorityqueue * const ppq, const int size) <br/>{< br/> If (size <= 0) <br/> return False; <br/> * ppq = (struct priorityqueue *) malloc (sizeof (struct priorityqueue); <br/> If (null = * ppq) <br/> return false; <br/> (* ppq)-> heap = (prioritynode *) malloc (sizeof (prioritynode) * (size + 1 )); <br/> If (null = (* ppq)-> heap) <br/>{< br/> free (* ppq); <br/> return false; <br/>}< br/> (* ppq)-> current = 0; <br/> (* ppq)-> size = size; </P> <p> return true; <br/>}</P> <p> bool isem Pty_p (const priorityqueue * const ppq) <br/>{< br/> If (0 = (* ppq)-> current) <br/> return true; <br/> else <br/> return false; <br/>}</P> <p> bool isfull_p (const priorityqueue * const ppq) <br/> {<br/> If (* ppq)-> current = (* ppq)-> size) <br/> return true; <br/> else <br/> return false; <br/>}</P> <p> bool insert_p (const priorityqueue * const ppq, const prioritynode PN) <br/>{< br/> If (true = Isfull_p (ppq) <br/> return false; <br/> (* ppq)-> heap [++ (* ppq)-> current] = pN; <br/> percolateup_p (* ppq)-> heap, (* ppq)-> current, (* ppq)-> current ); </P> <p> return true; <br/>}</P> <p> prioritynode deletemin_p (const priorityqueue * const ppq) <br/>{< br/> prioritynode record; </P> <p> If (isempty_p (ppq) <br/> return NULL; <br/> record = (* ppq)-> heap [1]; <br/> (* ppq)-> heap [1] = (* ppq)-> Heap [(* ppq)-> current --]; <br/> percolatedown_p (* ppq)-> heap, 1, (* ppq)-> current ); </P> <p> return record; <br/>}</P> <p> bool increasekey_p (const priorityqueue * const ppq, const int position, const item delta) <br/>{< br/> If (position <1 | position> (* ppq)-> current | Delta <= 0) <br/> return false; <br/> (* ppq)-> heap [position]-> item + = delta; <br/> percolatedown_p (* ppq)-> heap, Position, (* ppq)-> current); </P> <p> return true; <br/>}</P> <p> bool decreasekey_p (const priorityqueue * const ppq, const int position, const item delta) <br/>{< br/> If (position <1 | position> (* ppq)-> current | Delta <= 0) <br/> return false; <br/> (* ppq)-> heap [position]-> item-= delta; <br/> percolateup_p (* ppq)-> heap, position, (* ppq)-> current); </P> <p> return true; <br/>}</P> <p> Void release_p (const priorityqueue * const ppq) <br/>{< br/> free (* ppq)-> heap); <br/> free (* ppq ); <br/>}</P> <p>/* local function definition */</P> <p> static bool percolateup_p (prioritynode * const heap, const int position, const int size) <br/>{< br/> prioritynode temp; <br/> int I; </P> <p> If (position <1 | position> size) <br/> return false; <br/> temp = heap [position]; <br/> for (I = position; parent (I)> = 1 & Heap [Parent (I)]-> item> temp-> item; I = parent (I )) <br/> heap [I] = heap [Parent (I)]; <br/> heap [I] = temp; </P> <p> return true; <br/>}</P> <p> static bool percolatedown_p (prioritynode * const heap, const int position, const int size) <br/> {<br/> prioritynode temp; <br/> int I, child; </P> <p> If (position <1 | position> size) <br/> return false; <br/> temp = heap [position]; <br/> for (I = Position; left (I) <= size; I = Child) <br/>{< br/> child = left (I); <br/> If (child! = Size & heap [child]-> item> heap [Child + 1]-> item) <br/> child = right (I ); <br/> If (temp-> item> heap [child]-> item) <br/> heap [I] = heap [child]; <br/> else <br/> break; <br/>}< br/> heap [I] = temp; </P> <p> return true; <br/>}