Algorithm learning-binary heap implementation of priority queue

Priorityquenue

The priority queue is the ADT of the job scheduling class, which is implemented using the binary heap.
The priority queue has at least two operations: insert and deletemin ).

Insert operation diagram:

• Image Source: www.educity.cn

Delete operation diagram:

• Source: www.cfanz.cn

Code implementation:

//// Main. CPP // binaryheap /// created by Alps on 14-8-17. // copyright (c) 2014 Chen. all rights reserved. // # include <iostream> # include "binaryheap. H "// # define elementtype intusing namespace STD; priorityquenue initialize (INT maxnum) {priorityquenue P = (Inline) malloc (sizeof (struct heapstruct); If (P = NULL) {// error ("can't malloc memory"); exit (1);} p-> elements = (elementtype *) malloc (Maxnum * sizeof (elementtype); If (p-> elements = NULL) {// error ("can't malloc memory"); exit (1 );} p-> capacity = maxnum; P-> size = 0; P-> elements [0] = 0; return P;} void destory (priorityquenue p) {If (P! = NULL & P-> elements! = NULL) {free (p-> elements); free (p) ;}} void makeempty (priorityquenue p) {If (P! = NULL & P-> elements! = NULL) {free (p-> elements); P-> elements = (elementtype *) malloc (p-> capacity * sizeof (elementtype )); p-> size = 0 ;}} int isempty (priorityquenue p) {If (P! = NULL) {return p-> size = 0;} else {return 1 ;}} int isfull (priorityquenue p) {If (P! = NULL) {return p-> size = p-> capacity-1 ;}else {// error ("P is not exist"); return 1 ;}} void insert (priorityquenue P, elementtype X) {int I = 0; If (! Isfull (p) {P-> elements [p-> size + 1] = x; P-> size ++; for (I = p-> size; p-> elements [I/2]> X; I/= 2) {P-> elements [I/2] = p-> elements [I] + P-> elements [I/2]; p-> elements [I] = p-> elements [I/2]-p-> elements [I]; p-> elements [I/2] = p-> elements [I/2] = p-> elements [I];} p-> elements [I] = x ;} else {// error ("The priorityquenue is already full"); Return ;}} elementtype findmin (priorityquenue p) {If (! Isempty (p) {return p-> elements [1];} else {return NULL;} elementtype deletemin (priorityquenue p) {elementtype minelement, lastelement; int temp; int I = 1; if (! Isempty (p) {minelement = p-> elements [1]; lastelement = p-> elements [p-> size]; for (I = 1; I * 2 <p-> size; I = temp) {temp = I * 2; If (temp! = P-> size) {If (p-> elements [temp] <p-> elements [temp + 1]) {P-> elements [I] = p-> elements [temp];} else {P-> elements [I] = p-> elements [temp + 1]; temp ++ ;}}if (lastelement <p-> elements [I]) {P-> elements [I] = lastelement; // P-> size --; break;} p-> elements [I] = lastelement; P-> size --; return minelement;} else {return NULL ;}} void min (elementtype &, elementtype & B, elementtype & C) {If (B <c) {// RET Urn A <C? A: C; If (B <A) {B = a + B; A = B-A; B = B-a ;}} else {If (C <) {c = A + C; A = C-A; C = C-A;} // return B <C? B: C ;}} void buildheap (priorityquenue p) {int I = 0; for (I = p-> size/2; I> 0; I --) {if (I * 2! = P-> size) {min (P-> elements [I], p-> elements [I * 2], p-> elements [I * 2 + 1]);} else {// P-> elements [I] = p-> elements [I] <p-> elements [I * 2]? P-> elements [I]: p-> elements [I * 2]; If (p-> elements [I]> P-> elements [I * 2]) {int TMP = p-> elements [I * 2]; P-> elements [I * 2] = p-> elements [I]; p-> elements [I] = TMP ;}}} int main (INT argc, const char * argv []) {priorityquenue P = initialize (20 ); // insert (p, 13); // insert (p, 21); // insert (p, 16); // insert (p, 24 ); // insert (p, 31); // insert (p, 19); // insert (p, 68); // insert (p, 65 ); // insert (p, 26); // insert (p, 32); // insert (p, 14); int A [] =, 68, 65, 26, 32, 14}; For (INT I = 0; I <11; I ++) {P-> elements [I + 1] = A [I];} p-> size = sizeof (a)/sizeof (INT); For (INT I = 1; I <= p-> size; I ++) {printf ("% d", p-> elements [I]);} printf ("\ n"); buildheap (p); // deletemin (P ); for (INT I = 1; I <= p-> size; I ++) {printf ("% d", p-> elements [I]);} printf ("\ n"); Return 0 ;}

The above is the main. cpp file.
The following is the binaryheap. h file code:

 
//// Binaryheap. h // binaryheap /// created by Alps on 14-8-17. // copyright (c) 2014 Chen. all rights reserved. // # ifndef define # define elementtype intstruct heapstruct; typedef heapstruct * struct; incluinitialize (INT maxnum); void destory (inclup); void makeempty (priorityquenue P ); void insert (priorityquenue P); elementtype deletemin (priorityquenue P); elementtype findmin (partition P); int isempty (priorityquenue P); int isfull (priorityquenue P ); struct heapstruct {int capacity; int size; elementtype * elements ;};# endif