循环队列

#include <stdio.h>
#include <stdlib.h>

//Real capacity is CircularQueueMaxSize -1
#define CircularQueueMaxSize 1000

typedef int ElementType;

struct CircularQueue
{
    ElementType QueueData[CircularQueueMaxSize];
    int Front;
    int Rear;
};

int CircularQueueIsEmpty(struct CircularQueue *Queue)
{
    return (Queue -> Front == Queue -> Rear);
}

int CircularQueueIsFull(struct CircularQueue *Queue)
{
    return ((Queue -> Rear + 1) % CircularQueueMaxSize == Queue -> Front);
}

struct CircularQueue *CircularQueueInit()
{
    struct CircularQueue *Queue;
    Queue = malloc(sizeof(struct CircularQueue));
    
    Queue -> Front = Queue -> Rear = 0;
    
    return Queue;
}

//if Queue is full,return 1 
int CircularQueueEnqueue(struct CircularQueue *Queue,ElementType ToBeEnqueue)
{
    if(CircularQueueIsFull(Queue))
    {
        return 1;
    }
    else
    {
        Queue -> Rear = (Queue -> Rear + 1) % CircularQueueMaxSize;
        Queue -> QueueData[Queue -> Rear] = ToBeEnqueue;
    }
    return 0;
}

//if Queue is empty,return 1 
ElementType CircularQueueTop(struct CircularQueue *Queue)
{
    if(CircularQueueIsEmpty(Queue))
    {
        return 1;
    }
    else
    {
        return Queue -> QueueData[(Queue -> Front + 1) % CircularQueueMaxSize];
    }
    return 0;
}

//if Queue is empty,return 1 
int CircularQueueDequeue(struct CircularQueue *Queue)
{
    if(CircularQueueIsEmpty(Queue))
    {
        return 1;
    }
    else
    {
        Queue -> Front = (Queue -> Front + 1) % CircularQueueMaxSize;
        return 0;
    }
}

int MakeCircularQueueEmpty(struct CircularQueue *Queue)
{
    Queue -> Front = Queue -> Rear = 0;
    
    return 0;
}

int CircularQueueDelete(struct CircularQueue *Queue)
{
    free(Queue);
    Queue = NULL;
    return 0;
}

int main()
{
    int test;
    int i;
    
    struct CircularQueue *Queue;
    Queue = CircularQueueInit();
    MakeCircularQueueEmpty(Queue);
    CircularQueueDelete(Queue);
    
    Queue = CircularQueueInit();
    test = CircularQueueTop(Queue);
    CircularQueueDequeue(Queue);
    
    CircularQueueEnqueue(Queue,39);
    test = CircularQueueTop(Queue);
    CircularQueueDequeue(Queue);
    printf("%d
",test);
    for(i = 1;i < 2000;i ++)
    {
        CircularQueueEnqueue(Queue,i);
    }
    for(i = 1;i < 500;i ++)
    {
        CircularQueueDequeue(Queue);
    }
    test = CircularQueueTop(Queue);
    CircularQueueDequeue(Queue);
    printf("%d
",test);
    return 0;
}