# C Program to Calculate Purchase Amount to be Paid after Discount

In this tutorial, we will learn about how to create a program in C that will ask from user to enter total shopping amount purchased in the shop, and then apply the discount as per the following discount criteria, then find and print the final amount that has to be paid by the customer after subtracting the discount amount:

• If user has purchased something that costs from Rs.101 to Rs.200, the discount will be 5%
• If user has purchased something that costs from Rs.201 to Rs.400, the discount will be 10%
• If user has purchased something that costs from Rs.401 to Rs.800, the discount will be 20%
• And if user has purchased something that costs above Rs.800, the total discount that will be applied on the whole purchase amount is 25%

Let's take a look at the program:

```// Write a program in C, which will accept the orignal
// purchase amount and compute the net or final purchase
// amount (after applying discount) that has to be paid
// by the customer for the purchase made by him/her
// The Discount rates are as follows:
//   Purchase Amount     Discount
//   >100 & <=200        5%
//   >200 & <=400        10%
//   >400 & <=800        20%
//   >800                25%
// -----------codescracker.com-----------

#include<stdio.h>
#include<conio.h>
int main()
{
float amount, discount, amountToBePaid;
printf("How much shopping amount you have done here ? ");
scanf("%f", &amount);
printf("\n");
if(amount<=100)
{
printf("You have to paid: Rs.%0.2f", amount);
}
else
{
if(amount>100 && amount<=200)
{
discount = (amount*5)/100;
amountToBePaid = amount-discount;
printf("After applying the discount, you have to paid: Rs.%0.2f", amountToBePaid);
}
else if(amount>200 && amount<=400)
{
discount = (amount*10)/100;
amountToBePaid = amount-discount;
printf("After applying the discount, you have to paid: Rs.%0.2f", amountToBePaid);
}
else if(amount>400 && amount<=800)
{
discount = (amount*20)/100;
amountToBePaid = amount-discount;
printf("After applying the discount, you have to paid: Rs.%0.2f", amountToBePaid);
}
else
{
discount = (amount*25)/100;
amountToBePaid = amount-discount;
printf("After applying the discount, you have to paid: Rs.%0.2f", amountToBePaid);
}
}
getch();
return 0;
}```

As the program was written under Code::Blocks IDE, therefore after successful build and run, here is the output you will get on your output screen. This is the first snapshot of the sample run: Now enter the total amount (original purchase amount) say Rs.150, that is customer has made a purchase of Rs.150 at the shop. Now press `ENTER` key to see the total cost (final cost) customer has to paid after applying the discount. Here is the second snapshot of the sample run: Let's take another sample run. This time, the customer made purchase of Rs.670. Here is the snapshot of the sample run: Here is another sample run, this time, the customer made purchase of Rs.2000: Here are some of the main steps used in above program:

• Use if statement to check whether the purchase amount is less than or equal to Rs.100 or not
• If it is, then just ask him/her to pay the orignal purchase amount as final purchase amount without applying any discount. As the discount starts only when the purchase amount exceeds Rs.100
• Otherwise if the purchase amount exceeds Rs.100, then apply the discount and ask him/her to pay the final or net amount after applying the discount
• Here first we have to calculate the discount amount. To calculate the discount amount, multiply the amount with discount percentage and divide it by 100 and then initialize it to a variable that hold the discount value say discount. And then minus the discount value from the original purchase amount and initialize it to another variable that hold the final amount that has to be paid by the customer say amountToBePaid.
• Finally print the value of amountToBePaid as output. Whatever the net or final amount will be, amountToBePaid variable holds it
• For example, let's suppose user has purchased few items that costs Rs.768. Or user has provided 768 as input
• As the given value is greater than 400 and less than or equal to 800, therefore the discount that will be applied on this purchase amount will be 20%
• Therefore, (amount*20)/100 or (768*20)/100 or (15360)/100 or 153.6 will be initialized to discount
• And amount-discount or 768-153.6 or 614.4 will be initialized to amountToBePaid
• Now print the value of amountToBePaid as output which will be the net amount that has to be paid by the customer

Tools
Calculator