C Program are closing automatically

Question

I created a C Program that will take all the order of the user then generate the grandtotal of the orders.

But when I will order another food, the program is closing automatically.

I don't know if this is about my getch or the breaks in my switch method. Sometimes, it will proceed to take another error but it automatically outputs "INVALID FOOD".

Here is my code:

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

void menu();
void foods();
void main();
char food;
int quantity;
float price;
float total;
float grandtotal;
int choice;

void main()
{
    clrscr();
    menu();

    foods();
    getch();
}

void menu(){

    food = ' ';
    quantity = 0;
    price = 0;
    total = 0;
    choice = 0;
    printf("Please select food from the following:
");
    printf(" B = Burger, F = French Fries, P = Pizza, S = Sandwiches 
");

    printf("Enter food:");
    scanf("%c", &food);
}

void foods(){
    switch(food)
    {
        case 'B':
            printf("You selected Burger!
");
            printf("Enter quantity:");
            scanf("%d", &quantity);
            price = 95.50;

            printf("
 Do you want to order more? [1] Yes [2] No:");
            scanf("%d", &choice);

            total = price*quantity;

            if(choice == 1){
                menu();
                break;
            }
            else if (choice == 2){
                grandtotal = grandtotal + total;
                printf("
 Total Price is: %0.2f", grandtotal);
                break;
            }

        case 'F':
            printf("You selected French Fries!
");
            printf("Enter quantity:");
            scanf("%d", &quantity);
            price = 47.75;

            printf("
 Do you want to order more? [1] Yes [2] No:");
            scanf("%d", &choice);

            total = price*quantity;
            if(choice == 1){
                menu();
                break;
            }
            else if (choice == 2){
                grandtotal = grandtotal + total;
                printf("
 Total Price is: %0.2f", grandtotal);
                break;
            }

        case 'P':
            printf("You selected French Pizza!
");
            printf("Enter quantity:");
            scanf("%d", &quantity);
            price = 105.00;

            printf("
 Do you want to order more? [1] Yes [2] No:");
            scanf("%d", &choice);

            total = price*quantity;
            if(choice == 1){
                menu();
                break;
            }
            else if (choice == 2){
                grandtotal = grandtotal + total;
                printf("
 Total Price is: %0.2f", grandtotal);
                break;
            }

        case 'S':
            printf("You selected Sandwiches
");
            printf("Enter quantity:");
            scanf("%d", &quantity);
            price = 75.50;

            printf("
 Do you want to order more? [1] Yes [2] No:");
            scanf("%d", &choice);

            total = price*quantity;
            if(choice == 1){
                main();
                break;
            }
            else if (choice == 2){
                grandtotal = grandtotal + total;
                printf("
 Total Price is: %0.2f", grandtotal);
                break;
            }

            default:
            printf("INVALID FOOD!");
            break;

    }
}

I wish someone could help or guide me. Thanks in advance.

Answer 1

In you code you have duplicated multiple times:

...
if(choice == 1){
   menu();
   break;
} ...
...

So when you choose choice = 1 then menu() get's displayed, and then the code breaks out of foods(). I think you meant to do the foods section again:

...
if(choice == 1){
   menu();
   foods();
   break;
} ...
...

Yet another problem in your code is the %c scanf modifier. It will not eat up leading whitespaces, so it will read a newline (inputted on the last scanf). Use a leading space " %c" to tell scanf to read up leading whitespaces and ignore the leading newline, in scanf(" %c", &food);

1. Indent your code.
2. Don't duplicate statements. The whole scanf(... &choice); if (choice == 1) ... else if (choice == 2) could be placed outside the while switch not beeing duplicated 4 times.
3. Nesting functions using recursive calls can make your stack run out. Better just use a while loop.
4. Try not to use global variables. They are misleading and lead to maintainable code.

A slightly modified version of you code with a bit of indententation, added a do ... while loop and removed global variables and code duplication, may look like this:

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

char menu(void);
float foods(char food);

void main()
{
    clrscr();

    float grandtotal = 0;

    int choice = 0;
    do {
        // print menu and choose the food
        char food = menu();
        // choose food quantity and get it's price
        float total = foods(food);

        // print the total price
        grandtotal = grandtotal + total;
        printf("
 Total Price is: %0.2f", grandtotal);

        // do you want to continue?
        printf("
 Do you want to order more? [1] Yes [2] No:");
        if (scanf("%d", &choice) != 1) {
            perror("scanf error");
            abort();
        }

        // continue until choice is equal to 1
    } while (choice != 1);
}

char menu(void)
{
    char food;
    printf("Please select food from the following:
");
    printf(" B = Burger, F = French Fries, P = Pizza, S = Sandwiches 
");
    printf("Enter food:");
    if (scanf(" %c", &food) != 1) {
        perror("scanf error");
        abort();
    }
    return food;
}

float foods(char food){
    float price = 0;
    switch (food) {
    case 'B':
        printf("You selected Burger!
");
        price = 95.50;
        break;
    case 'F':
        printf("You selected French Fries!
");
        price = 47.75;
        break;
    case 'P':
        printf("You selected French Pizza!
");
        price = 105.00;
        break;
    case 'S':
        printf("You selected Sandwiches
");
        price = 75.50;
        break;
    default:
        fprintf(stderr, "INVALID FOOD!
");
        abort();
    }

    printf("Enter quantity:");
    int quantity;
    if (scanf("%d", &quantity) != 1) {
        perror("scanf error");
        abort();
    }

    return (float)price * (float)quantity;
}