编写一段关于队列的C语言代码

以下是一个简单的队列实现的 C 语言代码：

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

#define MAX_SIZE 100

typedef struct {
    int front, rear;
    int data[MAX_SIZE];
} Queue;

Queue *createQueue() {
    Queue *queue = (Queue *) malloc(sizeof(Queue));
    queue->front = -1;
    queue->rear = -1;
    return queue;
}

int isFull(Queue *queue) {
    return queue->rear == MAX_SIZE - 1;
}

int isEmpty(Queue *queue) {
    return queue->front == -1 || queue->front > queue->rear;
}

void enqueue(Queue *queue, int value) {
    if (isFull(queue)) {
        printf("Queue is full\n");
        return;
    }
    queue->data[++queue->rear] = value;
    if (queue->front == -1) {
        queue->front = 0;
    }
}

int dequeue(Queue *queue) {
    if (isEmpty(queue)) {
        printf("Queue is empty\n");
        return -1;
    }
    int value = queue->data[queue->front++];
    if (queue->front > queue->rear) {
        queue->front = queue->rear = -1;
    }
    return value;
}

int main() {
    Queue *queue = createQueue();

    enqueue(queue, 10);
    enqueue(queue, 20);
    enqueue(queue, 30);

    printf("%d dequeued from queue\n", dequeue(queue));
    printf("%d dequeued from queue\n", dequeue(queue));

    enqueue(queue, 40);
    enqueue(queue, 50);

    printf("%d dequeued from queue\n", dequeue(queue));
    printf("%d dequeued from queue\n", dequeue(queue));
    printf("%d dequeued from queue\n", dequeue(queue));

    return 0;
}

这段代码实现了一个基本的队列，包括创建队列、判断队列是否为空、判断队列是否已满、入队、出队等基本操作。