C语言实现循环队列的头部插入、尾部插入、头部出队、尾部出队

#include 
#include 
#include 

typedef struct _queue
{
    int *buffer;
    unsigned int front;
    unsigned int rear;
    unsigned int size;
}queue;

//初始化循环队列
int initQueue(queue *Q, unsigned int size)
{
    Q->buffer = (int*)malloc(size * sizeof (int));
    if(!Q->buffer)
        return 0;
    Q->size = size;
    Q->front = 0;
    Q->rear = 0;

    return 1;
}

//队列尾部插入
int push_back(queue *Q, int n)
{
    if((Q->rear + 1) % Q->size == Q->front)
        return 0;

    Q->buffer[Q->rear] = n;
    Q->rear = (Q->rear + 1) % Q->size;
    return 1;
}

//队列头部插入
int push_front(queue *Q, int n)
{
    if((Q->front - 1 + Q->size) % Q->size == Q->rear)
        return 0;

    Q->front = (Q->front - 1 + Q->size) % Q->size;
    Q->buffer[Q->front] = n;

    return 1;
}

//队列头部出队
int pop_front(queue *Q, int *x)
{
    if(Q->front == Q->rear)
        return 0;

    *x = Q->buffer[Q->front];
    Q->front = (Q->front + 1) % Q->size;
    return 1;
}

//队尾出队
int pop_back(queue *Q, int *x)
{
   if(Q->front == Q->rear)
       return 0;

   Q->rear = (Q->rear - 1 + Q->size) % Q->size;
   *x = Q->buffer[Q->rear];

   return 1;
}

//遍历队列
void traverseQueue(queue *Q)
{
    unsigned int idx = Q->front;
    while(idx != Q->rear)
    {
        printf("%d ", Q->buffer[idx]);
        idx = (idx+1) % Q->size;
    }
    printf("\r\n");
}

//是否是空队列
bool isEmptyQueue(queue *Q)
{
    return Q->front == Q->rear;
}

//是否是满队列
bool isFullQueue(queue *Q)
{
    return (Q->rear + 1) % Q->size == Q->front;
}

//清除队列元素
void clearQueue(queue *Q)
{
    Q->front = 0;
    Q->rear = 0;
}

//释放队列
void deleteQueue(queue *Q)
{
    free(Q->buffer);
}

int main()
{
    queue Q;
    int x;
    initQueue(&Q, 5);
    for(int i = 0; i < 5; i++)
        push_back(&Q, i);

    pop_front(&Q, &x);
    printf("%d\r\n", x);
    traverseQueue(&Q);
    deleteQueue(&Q);
    return 0;
}