编写c语言代码实现循环队列

为了实现循环队列，我们需要定义一个数组和两个指针front和rear。front指向队列的第一个元素，rear指向队列的最后一个元素。当队列为空时，front和rear都指向-1。当队列满时，rear指向最后一个元素，front指向第一个元素的前一个位置。下面是一个简单的C语言实现循环队列的代码：

#define MAX_SIZE 10

int queue[MAX_SIZE];
int front = -1, rear = -1;

void enqueue(int data) {
    if ((front == 0 && rear == MAX_SIZE - 1) || (rear == front - 1)) {
        printf("Queue is full\n");
        return;
    }
    else if (front == -1 && rear == -1) {
        front = rear = 0;
    }
    else if (rear == MAX_SIZE - 1 && front != 0) {
        rear = 0;
    }
    else {
        rear++;
    }
    queue[rear] = data;
}

int dequeue() {
    if (front == -1 && rear == -1) {
        printf("Queue is empty\n");
        return -1;
    }
    int data = queue[front];
    if (front == rear) {
        front = rear = -1;
    }
    else if (front == MAX_SIZE - 1) {
        front = 0;
    }
    else {
        front++;
    }
    return data;
}