用C++写一个汽车租赁管理系统

好的，下面是一个简单的汽车租赁管理系统的C代码示例：

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define MAX_SIZE 100

struct Car{
    int car_id;
    char car_name[20];
    char car_type[20];
    int car_price;
    int car_rented;
};

struct Car cars[MAX_SIZE];
int num_cars = 0;

void add_car(){
    struct Car new_car;
    printf("Enter car id: ");
    scanf("%d",&new_car.car_id);
    printf("Enter car name: ");
    scanf("%s",new_car.car_name);
    printf("Enter car type: ");
    scanf("%s",new_car.car_type);
    printf("Enter car price per day: ");
    scanf("%d",&new_car.car_price);
    new_car.car_rented = 0;
    cars[num_cars] = new_car;
    num_cars++;
    printf("Car added successfully!\n");
}

void list_available_cars(){
    printf("Available cars:\n");
    for(int i=0;i<num_cars;i++){
        if(cars[i].car_rented == 0){
            printf("%d - %s (%s) - %d$ per day\n",cars[i].car_id,cars[i].car_name,cars[i].car_type,cars[i].car_price);
        }
    }
}

void rent_car(){
    int id;
    printf("Enter car id to rent: ");
    scanf("%d",&id);
    for(int i=0;i<num_cars;i++){
        if(cars[i].car_id == id){
            if(cars[i].car_rented == 1){
                printf("Car already rented!\n");
                return;
            }
            cars[i].car_rented = 1;
            printf("Car rented successfully!\n");
            return;
        }
    }
    printf("Invalid car id!\n");
}

void return_car(){
    int id;
    printf("Enter car id to return: ");
    scanf("%d",&id);
    for(int i=0;i<num_cars;i++){
        if(cars[i].car_id == id){
            if(cars[i].car_rented == 0){
                printf("Car not rented!\n");
                return;
            }
            cars[i].car_rented = 0;
            printf("Car returned successfully!\n");
            return;
        }
    }
    printf("Invalid car id!\n");
}

int main(){
    int choice;
    while(1){
        printf("1. Add car\n");
        printf("2. List available cars\n");
        printf("3. Rent car\n");
        printf("4. Return car\n");
        printf("5. Exit\n");
        printf("Enter your choice: ");
        scanf("%d",&choice);
        switch(choice){
            case 1: add_car();
                    break;
            case 2: list_available_cars();
                    break;
            case 3: rent_car();
                    break;
            case 4: return_car();
                    break;
            case 5: exit(0);
            default: printf("Invalid choice!\n");
        }
    }
    return 0;
}

这个代码实现了以下功能：

- 添加汽车信息
- 列出可租用汽车
- 租用汽车
- 归还汽车
- 退出系统

你可以根据自己的需求和实际情况对代码进行适当的修改和完善。