队列的ADT

 1 #ifndef QUEUE_H_INCLUDED
 2 #define QUEUE_H_INCLUDED
 3 #include <stdbool.h>
 4 
 5 typedef struct queue QUEUE;
 6 
 7 QUEUE* createQueue(void);
 8 QUEUE* destroyQueue(QUEUE* queue);
 9 
10 bool dequeue(QUEUE* queue, void** itemPtr);
11 bool enqueue(QUEUE* queue, void* itemPtr);
12 bool queueFront(QUEUE* queue, void** itemPtr);
13 bool queueRear(QUEUE* queue, void** itemPtr);
14 int queueCount(QUEUE* queue);
15 
16 bool emptyQueue(QUEUE* queue);
17 bool fullQueue(QUEUE* queue);
18 
19 #endif // QUEUE_H_INCLUDED

  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 #include "Queue.h"
  4 
  5 typedef struct node
  6 {
  7     void* dataPtr;
  8     struct node* next;
  9 } QUEUE_NODE;
 10 
 11 struct queue
 12 {
 13     QUEUE_NODE* front;
 14     QUEUE_NODE* rear;
 15     int count;
 16 };
 17 
 18 QUEUE* createQueue(void)
 19 {
 20     QUEUE* queue;
 21 
 22     queue = (QUEUE*)malloc(sizeof(QUEUE));
 23     if(queue){
 24         queue->front = NULL;
 25         queue->rear = NULL;
 26         queue->count = 0;
 27     }
 28     return queue;
 29 }
 30 
 31 QUEUE* destroyQueue(QUEUE* queue)
 32 {
 33     QUEUE_NODE* deletePtr;
 34 
 35     if(queue){
 36         while(queue->front != NULL){
 37             free(queue->front->dataPtr);
 38             deletePtr = queue->front;
 39             queue->front = queue->front->next;
 40             free(deletePtr);
 41         }
 42         free(queue);
 43     }
 44     return NULL;
 45 }
 46 
 47 bool dequeue(QUEUE* queue, void** itemPtr)
 48 {
 49     QUEUE_NODE* deleteLoc;
 50 
 51     if(!queue->count)
 52         return false;
 53 
 54     *itemPtr = queue->front->dataPtr;
 55     deleteLoc = queue->front;
 56     if(queue->count == 1)
 57         queue->rear = queue->front = NULL;
 58     else
 59         queue->front = queue->front->next;
 60     (queue->count)--;
 61     free(deleteLoc);
 62 
 63     return true;
 64 }
 65 bool enqueue(QUEUE* queue, void* itemPtr)
 66 {
 67     QUEUE_NODE* newPtr;
 68 
 69     if(!(newPtr = (QUEUE_NODE*)malloc(sizeof(QUEUE_NODE))))
 70         return false;
 71 
 72     newPtr->dataPtr = itemPtr;
 73     newPtr->next = NULL;
 74 
 75     if(queue->count == 0)
 76         queue->front = newPtr;
 77     else
 78         queue->rear->next = newPtr;
 79 
 80     (queue->count)++;
 81     queue->rear = newPtr;
 82     return true;
 83 }
 84 bool queueFront(QUEUE* queue, void** itemPtr)
 85 {
 86     if(!queue->count)
 87         return false;
 88     else
 89     {
 90         *itemPtr = queue->front->dataPtr;
 91         return true;
 92     }
 93 }
 94 bool queueRear(QUEUE* queue, void** itemPtr)
 95 {
 96     if(!queue->count)
 97         return false;
 98      else
 99     {
100         *itemPtr = queue->rear->dataPtr;
101         return true;
102     }
103 }
104 int queueCount(QUEUE* queue)
105 {
106     return queue->count;
107 }
108 
109 bool emptyQueue(QUEUE* queue)
110 {
111     return(queue->count == 0);
112 }
113 bool fullQueue(QUEUE* queue)
114 {
115     QUEUE_NODE* temp;
116 
117     temp = (QUEUE_NODE*)malloc(sizeof(*(queue->rear)));
118     if(temp){
119         free(temp);
120         return false;
121     }
122     return true;
123 }