帮忙用C语言写一个代码

好的，我可以给你提供一个简单的停车场管理系统的C语言代码，你可以根据需要进行修改和扩展。

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

#define CAR_NUM 10 // 停车场车位数
#define WAIT_NUM 5 // 等待队列长度

// 车辆结构体
typedef struct car {
    char plate_num[10]; // 车牌号
    time_t arrival_time; // 到达时间
    int park_time; // 停留时间
} Car;

// 停车场结构体
typedef struct parking_lot {
    Car *cars[CAR_NUM]; // 车辆指针数组
    int count; // 当前停车量
} ParkingLot;

// 等待队列结构体
typedef struct wait_queue {
    Car *cars[WAIT_NUM]; // 车辆指针数组
    int count; // 当前等待量
    int head; // 队头
    int tail; // 队尾
} WaitQueue;

// 初始化停车场
void init_parking_lot(ParkingLot *parking_lot) {
    parking_lot->count = 0;
    for (int i = 0; i < CAR_NUM; i++) {
        parking_lot->cars[i] = NULL;
    }
}

// 初始化等待队列
void init_wait_queue(WaitQueue *wait_queue) {
    wait_queue->count = 0;
    wait_queue->head = 0;
    wait_queue->tail = 0;
    for (int i = 0; i < WAIT_NUM; i++) {
        wait_queue->cars[i] = NULL;
    }
}

// 停车
void park_car(ParkingLot *parking_lot, WaitQueue *wait_queue, Car *car) {
    if (parking_lot->count < CAR_NUM) { // 停车场未满
        // 找到空位停车
        for (int i = 0; i < CAR_NUM; i++) {
            if (parking_lot->cars[i] == NULL) {
                parking_lot->cars[i] = car;
                parking_lot->count++;
                printf("车牌号为 %s 的车辆已停入停车场，停车位为 %d\n", car->plate_num, i);
                return;
            }
        }
    } else { // 停车场已满
        if (wait_queue->count < WAIT_NUM) { // 等待队列未满
            wait_queue->cars[wait_queue->tail] = car;
            wait_queue->count++;
            wait_queue->tail = (wait_queue->tail + 1) % WAIT_NUM;
            printf("车牌号为 %s 的车辆已停入等待队列，等待序号为 %d\n", car->plate_num, wait_queue->count);
            return;
        } else { // 等待队列已满
            printf("车牌号为 %s 的车辆无法停入停车场，也无法进入等待队列\n", car->plate_num);
            return;
        }
    }
}

// 取车
void take_car(ParkingLot *parking_lot, WaitQueue *wait_queue, char *plate_num) {
    // 在停车场中查找车辆
    for (int i = 0; i < CAR_NUM; i++) {
        if (parking_lot->cars[i] != NULL && strcmp(parking_lot->cars[i]->plate_num, plate_num) == 0) {
            // 计算停车费用
            time_t now = time(NULL);
            int park_time = (int)(now - parking_lot->cars[i]->arrival_time);
            int fee = park_time / 60 * 5;
            printf("车牌号为 %s 的车辆已从停车场取出，停留时间为 %d 分钟，停车费用为 %d 元\n", plate_num, park_time, fee);
            // 从停车场中移除该车辆
            free(parking_lot->cars[i]);
            parking_lot->cars[i] = NULL;
            parking_lot->count--;
            // 从等待队列中取出一辆车进入停车场
            if (wait_queue->count > 0) {
                int head = wait_queue->head;
                park_car(parking_lot, wait_queue, wait_queue->cars[head]);
                wait_queue->cars[head] = NULL;
                wait_queue->count--;
                wait_queue->head = (head + 1) % WAIT_NUM;
            }
            return;
        }
    }
    // 在等待队列中查找车辆
    for (int i = 0; i < wait_queue->count; i++) {
        int index = (wait_queue->head + i) % WAIT_NUM;
        if (wait_queue->cars[index] != NULL && strcmp(wait_queue->cars[index]->plate_num, plate_num) == 0) {
            printf("车牌号为 %s 的车辆已从等待队列中移除\n", plate_num);
            free(wait_queue->cars[index]);
            wait_queue->cars[index] = NULL;
            wait_queue->count--;
            return;
        }
    }
    // 没有找到该车辆
    printf("未找到车牌号为 %s 的车辆\n", plate_num);
}

// 查询停车场状态
void query_parking_lot(ParkingLot *parking_lot) {
    printf("当前停车场状态：已停车辆数：%d，空闲车位数：%d\n", parking_lot->count, CAR_NUM - parking_lot->count);
}

// 查询等待队列状态
void query_wait_queue(WaitQueue *wait_queue) {
    printf("当前等待队列状态：等待车辆数：%d\n", wait_queue->count);
}

// 测试程序
int main() {
    ParkingLot parking_lot;
    WaitQueue wait_queue;
    init_parking_lot(&parking_lot);
    init_wait_queue(&wait_queue);

    // 停车
    Car car1 = {"京A12345", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car1);

    Car car2 = {"京B67890", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car2);

    Car car3 = {"京C24680", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car3);

    Car car4 = {"京D13579", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car4);

    Car car5 = {"京E97531", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car5);

    Car car6 = {"京F86420", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car6);

    Car car7 = {"京G75319", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car7);

    // 查询停车场状态和等待队列状态
    query_parking_lot(&parking_lot);
    query_wait_queue(&wait_queue);

    // 取车
    take_car(&parking_lot, &wait_queue, "京D13579");

    // 查询停车场状态和等待队列状态
    query_parking_lot(&parking_lot);
    query_wait_queue(&wait_queue);

    // 停车
    Car car8 = {"京H24680", time(NULL), 0};
    park_car(&parking_lot, &wait_queue, &car8);

    // 查询停车场状态和等待队列状态
    query_parking_lot(&parking_lot);
    query_wait_queue(&wait_queue);

    // 取车
    take_car(&parking_lot, &wait_queue, "京C24680");

    // 查询停车场状态和等待队列状态
    query_parking_lot(&parking_lot);
    query_wait_queue(&wait_queue);

    return 0;
}

这个代码实现了停车、取车、查询停车场状态和等待队列状态等基本功能。你可以根据需要进行修改和扩展。