用c语言写一个电子点餐系统

好的，电子点餐系统是一个比较复杂的系统，需要考虑到很多方面，比如菜品信息的存储、订单的生成和管理、支付和结账等等。以下是一个简单的电子点餐系统的代码示例：

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

#define MAX_DISHES 100

typedef struct dish {
    char name[50];
    float price;
    int quantity;
} Dish;

Dish dishes[MAX_DISHES];
int num_dishes = 0;

void add_dish() {
    Dish new_dish;
    printf("Enter the name of the dish: ");
    scanf("%s", new_dish.name);
    printf("Enter the price of the dish: ");
    scanf("%f", &new_dish.price);
    printf("Enter the quantity of the dish: ");
    scanf("%d", &new_dish.quantity);
    dishes[num_dishes] = new_dish;
    num_dishes++;
}

void view_dishes() {
    printf("Dishes available:\n");
    for (int i = 0; i < num_dishes; i++) {
        printf("%s - $%.2f - %d available\n", dishes[i].name, dishes[i].price, dishes[i].quantity);
    }
}

void place_order() {
    int order[MAX_DISHES] = {0};
    float total = 0;
    printf("Enter the number of dishes you want to order: ");
    int num_orders;
    scanf("%d", &num_orders);
    for (int i = 0; i < num_orders; i++) {
        printf("Enter the name of dish #%d: ", i+1);
        char dish_name[50];
        scanf("%s", dish_name);
        for (int j = 0; j < num_dishes; j++) {
            if (strcmp(dishes[j].name, dish_name) == 0) {
                printf("Enter the quantity of dish #%d: ", i+1);
                int quantity;
                scanf("%d", &quantity);
                if (quantity > dishes[j].quantity) {
                    printf("Sorry, we don't have enough %s. Please choose a smaller quantity.\n", dishes[j].name);
                } else {
                    order[j] = quantity;
                    total += quantity * dishes[j].price;
                }
                break;
            }
        }
    }
    printf("Your order:\n");
    for (int i = 0; i < num_dishes; i++) {
        if (order[i] > 0) {
            printf("%dx %s - $%.2f\n", order[i], dishes[i].name, dishes[i].price);
        }
    }
    printf("Total: $%.2f\n", total);
}

int main() {
    int choice;
    do {
        printf("1. Add a new dish\n");
        printf("2. View dishes available\n");
        printf("3. Place an order\n");
        printf("4. Exit\n");
        printf("Enter your choice: ");
        scanf("%d", &choice);
        switch (choice) {
            case 1:
                add_dish();
                break;
            case 2:
                view_dishes();
                break;
            case 3:
                place_order();
                break;
            case 4:
                printf("Goodbye!\n");
                break;
            default:
                printf("Invalid choice!\n");
                break;
        }
    } while (choice != 4);
    return 0;
}

这个程序使用了结构体来存储菜品信息，包括名称、价格和数量。用户可以选择添加新菜品、查看现有菜品和下订单。在下订单的过程中，程序会提示用户输入想要点的菜品名称和数量，并且会检查库存是否充足。如果库存不够，程序会提示用户重新输入。最后，程序会输出订单的详细信息和总价。