How to call functions in C - c

Question

I'm working on my final project for my intro to programming class and the assignment is to create a code that will display a menu and will ask the user to enter a choice. After that it will display the total for the order and the name of the item the user chose.
Here's my code:
#include <stdio.h>
#include <stdlib.h>
#define TEQUENOS_PRICE 5.00
#define AREPA_PRICE 3.00
#define CACHAPA_PRICE 2.50
#define EMPANADA_PRICE 2.00
#define SODA_PRICE 0.80
#define QUESILLO_PRICE 1.70
#define DULCE_DE_LECHE_PRICE 1.20
int main()
{
int choice = 0, tequenos = 0, arepa = 0, cachapa = 0, empanada = 0;
int soda = 0, quesillo = 0, dulceDeLeche = 0;
double sum = 0.0, totalPrice;
printf("Welcome to Daniela's Venezuelan emporium.\n");
printf("\nMay I take your order please?\n");
do
{
printf("\n\tMenu");
printf("\n1. Tequenos (5 ct.)\t $%5.2lf", TEQUENOS_PRICE);
printf("\n2. Arepa\t\t $%5.2lf", AREPA_PRICE);
printf("\n3. Cachapa\t\t $%5.2lf", CACHAPA_PRICE);
printf("\n4. Empanada\t\t $%5.2lf", EMPANADA_PRICE);
printf("\n5. Soda \t\t $%5.2lf", SODA_PRICE);
printf("\n6. Quesillo\t\t $%5.2lf", QUESILLO_PRICE);
printf("\n7. Dulce de Leche\t $%5.2lf", DULCE_DE_LECHE_PRICE);
printf("\n8. Done with this order.\n");
printf("\nEnter Item: ");
scanf("%i", &choice);
switch (choice)
{
case 1:
sum += TEQUENOS_PRICE;
tequenos++;
break;
case 2:
sum += AREPA_PRICE;
arepa++;
break;
case 3:
sum += CACHAPA_PRICE;
cachapa++;
break;
case 4:
sum += EMPANADA_PRICE;
empanada++;
break;
case 5:
sum += SODA_PRICE;
soda++;
break;
case 6:
sum += QUESILLO_PRICE;
quesillo++;
break;
case 7:
sum += DULCE_DE_LECHE_PRICE;
dulceDeLeche++;
break;
case 8:
break;
default:
printf("\n\t***ERROR: This is not on the menu.\n");
}
printf("\nTotal so far: $%.2lf\n", sum);
} while (choice != 8);
printf("\nThat's: ");
if (choice = 1)
{
printf(" %i Tequenos\n", tequenos);
}
if (choice = 2)
{
printf("\t %i Arepa\n", arepa);
}
if (choice = 3)
{
printf("\t %i Cachapa\n", cachapa);
}
if (choice = 4)
{
printf("\t %i Empanada\n", empanada);
}
if (choice = 5)
{
printf("\t %i Soda\n", soda);
}
if (choice = 6)
{
printf("\t %i Quesillo\n", quesillo);
}
if (choice = 7)
{
printf("\t %i Dulce De Leche\n", dulceDeLeche);
}
totalPrice = sum;
printf("\nYour total is $%.2lf\n", totalPrice);
printf("\nThank you for coming to Daniela's Venezuelan Emporium.");
printf("\nCome back soon!\n");
system("pause");
return 0;
}
The code works fine but my professor told me that I needed to call functions throughout the entire code, and that main should only be calling other functions. I have been trying but is really confusing for me and I do not know how to do it. I would really appreciate it if you guys could help me.
Thanks!

Answer 1

Here's your code, refactored slightly to break the major parts of your program out into separate functions.
#include <stdio.h>
#include <stdlib.h>
#define TEQUENOS_PRICE 5.00
#define AREPA_PRICE 3.00
#define CACHAPA_PRICE 2.50
#define EMPANADA_PRICE 2.00
#define SODA_PRICE 0.80
#define QUESILLO_PRICE 1.70
#define DULCE_DE_LECHE_PRICE 1.20
int tequenos = 0,
arepa = 0,
cachapa = 0,
empanada = 0,
soda = 0,
quesillo = 0,
dulceDeLeche = 0;
double sum = 0.0;
void print_header()
{
printf("Welcome to Daniela's Venezuelan emporium.\n");
printf("\nMay I take your order please?\n");
}
int get_menu_choice()
{
int choice;
printf("\n\tMenu");
printf("\n1. Tequenos (5 ct.)\t $%5.2lf", TEQUENOS_PRICE);
printf("\n2. Arepa\t\t $%5.2lf", AREPA_PRICE);
printf("\n3. Cachapa\t\t $%5.2lf", CACHAPA_PRICE);
printf("\n4. Empanada\t\t $%5.2lf", EMPANADA_PRICE);
printf("\n5. Soda \t\t $%5.2lf", SODA_PRICE);
printf("\n6. Quesillo\t\t $%5.2lf", QUESILLO_PRICE);
printf("\n7. Dulce de Leche\t $%5.2lf", DULCE_DE_LECHE_PRICE);
printf("\n8. Done with this order.\n");
printf("\nEnter Item: ");
scanf("%i", &choice);
return choice;
}
void process_menu_choice(int choice)
{
switch (choice)
{
case 1:
sum += TEQUENOS_PRICE;
tequenos++;
break;
case 2:
sum += AREPA_PRICE;
arepa++;
break;
case 3:
sum += CACHAPA_PRICE;
cachapa++;
break;
case 4:
sum += EMPANADA_PRICE;
empanada++;
break;
case 5:
sum += SODA_PRICE;
soda++;
break;
case 6:
sum += QUESILLO_PRICE;
quesillo++;
break;
case 7:
sum += DULCE_DE_LECHE_PRICE;
dulceDeLeche++;
break;
case 8:
break;
default:
printf("\n\t***ERROR: This is not on the menu.\n");
}
printf("\nTotal so far: $%.2lf\n", sum);
}
void take_order()
{
do
{
choice = get_menu_choice();
process_menu_choice(choice);
} while (choice != 8);
}
void print_total_for(char *item_type, int item_count)
{
if(item_count > 0)
printf(" %i %s\n", item_count, item_type);
}
int print_total(double totalPrice)
(
printf("\nYour total is $%.2lf\n", totalPrice);
printf("\nThank you for coming to Daniela's Venezuelan Emporium.");
printf("\nCome back soon!\n");
}
void print_total_header()
{
printf("\nThat's: ");
}
int main()
{
int choice = 0;
print_header();
take_order();
print_total_header();
print_total_for("Tequenos", tequenos);
print_total_for("Arepa", arepa);
print_total_for("Cachapa", cachapa);
print_total_for("Empanada", empanada);
print_total_for("Soda", soda);
print_total_for("Quesillo", quesillo);
print_total_for("Dulce De Leche", dulceDeLeche);
print_total(sum);
system("pause");
return 0;
}
Note: not compiled or tested. And if you copy this code, hand it in as your own, and your instructor flunks you for doing so - that's on you.
Best of luck.