C: Calculate Order Price Based On User's Input.
https://github.com/pereiradaniel/beginning_c/blob/master/ch2/exercises/2_3/exercise2_3.c
// Exercise 2-3
// Daniele Grech Pereira 22 November 2022
// You’re selling a product that’s available in two versions: type 1 is a
// standard version priced at $3.50, and type 2 is a deluxe version priced at $5.50.
// Write a program using only what you’ve learned up to now that prompts for the user to
// enter the product type and a quantity, and then calculates and outputs the price for
// the quantity entered.
#include <stdio.h>
#include <ctype.h> // toupper
#include <limits.h> // INT_MAX
// FIXED PRODUCT PRICES:
#define TYPE1 3.5f // Type1 price
#define TYPE2 5.5f // Type2 price
// A function that returns the calculated the price.
double calculatePrice(int input, int quantity);
// A function that validates a user's input.
int checkInput(int input, int min, int max);
// A function that returns the user's validated input.
int getInput(char* msg, int min, int max);
int main(int argc, char* argv[])
{
// Set and initialize vars for main program:
int type = 0, quantity = 0; // Vars for storing user input.
double price = 0; // Stores calculated results.
char repeat = 'Y'; // Loop var for main program to repeat.
// Main program loop:
while (toupper(repeat) == 'Y')
{
// Get type from user, can be either 1 or 2:
type = getInput("Select product type (1 or 2): ", 1, 2);
// Get quantity from user, can be from 1 to largest possible INT value:
quantity = getInput("Select quantity: ", 1, INT_MAX);
// Display user's selection before calculating:
printf("\nProduct type %d selected @ %d units.", type, quantity);
// Calculate price based on user's input:
price = calculatePrice(type, quantity);
// Display final results:
printf("\n\nRESULTS:\nProduct type: %d, quantity: %d, total: $%.2f\n", type, quantity, price);
// Ask if user wants to repeat the main program:
printf("\nAgain? (Y to repeat/any other key to quit) ");
scanf(" %c", &repeat);
};
return 0;
}
int getInput(char* msg, int min, int max)
{
int var = 0;
printf("%s", msg);
while(var == 0) {
scanf(" %d", &var);
var = checkInput(var, min, max);
}; // Loops until input is valid and not == 0
return var;
}
double calculatePrice(int input, int quantity)
{
double unit_price = 0;
if (input == 1)
unit_price = TYPE1;
if (input == 2)
unit_price = TYPE2;
return unit_price * (double)quantity;
}
int checkInput(int input, int min, int max)
{
int result = 0; // Return 0 if input is invalid.
if (input < min || input > max) // out of bounds, invalid!
printf("\nEnter a number between %d or %d!\n", min, max);
if (input >= min && input <= max) // inbounds, validate!
result = input;
return result;
}https://github.com/pereiradaniel/beginning_c/blob/master/ch2/exercises/2_3/exercise2_3.txt==662== Memcheck, a memory error detector ==662== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al. ==662== Using Valgrind-3.15.0 and LibVEX; rerun with -h for copyright info ==662== Command: ./exercise2_3 ==662== Select product type (1 or 2): 0 Enter a number between 1 or 2! 3 Enter a number between 1 or 2! 1 Select quantity: -1 Enter a number between 1 or 2147483647! 0 Enter a number between 1 or 2147483647! 2147483648 Enter a number between 1 or 2147483647! 1000 Product type 1 selected @ 1000 units. RESULTS: Product type: 1, quantity: 1000, total: $3500.00 ==662== ==662== HEAP SUMMARY: ==662== in use at exit: 0 bytes in 0 blocks ==662== total heap usage: 2 allocs, 2 frees, 2,048 bytes allocated ==662== ==662== All heap blocks were freed -- no leaks are possible ==662== ==662== For lists of detected and suppressed errors, rerun with: -s ==662== ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)
