I Have A Questio here

Why I can't print out the change due with my coding?anyone can solve it to me?

Code:

#include<stdio.h>
#include<math.h>

void main()
{
	int discount,set_of_combo;
	double total,a_payable,amount,cash;
	double g_tax,s_tax,change_due,a_a_payable;

	printf("Enter Number Of Combo Set : ");
	scanf("%d",&set_of_combo);

	printf("Enter Discount Voucher (RM) : ");
	scanf("%d",&discount);

	//calculation
	amount = set_of_combo*7.88;
	g_tax = amount * 6 / 100;
	s_tax = amount *10 / 100;
	total = g_tax + s_tax + amount;
	a_payable = total - discount;
	a_a_payable = a_payable;
        change_due = cash - a_a_payable

	printf("Good Day and Welcome To KLFC Sdn.Bhd");

	printf("R E C E I P T\n");
	printf("+-------------------------+------------------+-------------------+\n");
	printf("+       Description       |       Rate       |     Amount(RM)    |\n");
	printf("+-------------------------+------------------+-------------------+\n");
	printf("+      COMBO SET * %d      |       7.88       |        %.2f      |\n",set_of_combo,amount);
	printf("+      Goverment Tax      |        6%%        |        %.2f       |\n",g_tax);
	printf("+      Service Tax        |        10%%       |        %.2f       |\n",s_tax);
	printf("+-------------------------+------------------+-------------------+\n");
	printf("+               S U B   T O T A L            |          %.2f    |\n",total);
	printf("+============================================+===================|\n");
	printf("+      Discount Vouvher (RM)  %.2lf                               +\n",discount);//discount voucher
	printf("+                           --------                             |\n");
	printf("+      Amount Payable         %.2lf                              |\n",a_payable);//amount payable
	printf("+                           ========                             |\n");
	printf("+      Adjusted Amount Payable                      %.2lf          |\n",a_a_payable);//adjustment amount payable
	printf("=================================================================+\n");
	printf(" CASH ");
	scanf("%.2lf",&cash);
	printf(" Change Due:\n",change_due);
	printf("==================================================================\n");
	printf("               THANK YOU and HAVE A NICE DAY\n");

}

Presumably because you don't do

change_due = some_expression_involving_cash_and_amount_due;

i changed...the out come like this..

Enter Number Of Combo Set : 4
Enter Discount Voucher (RM) : 2
Good Day and Welcome To KLFC Sdn.BhdR E C E I P T
+-------------------------+------------------+-------------------+
+ Description | Rate | Amount(RM) |
+-------------------------+------------------+-------------------+
+ COMBO SET * 4 | 7.88 | 31.52 |
+ Goverment Tax | 6% | 1.89 |
+ Service Tax | 10% | 3.15 |
+-------------------------+------------------+-------------------+
+ S U B T O T A L | 36.56 |
+============================================+==== ===============|
+ Discount Vouvher (RM) 0.00 +
+ -------- |
+ Amount Payable 34.56 |
+ ======== |
+ Adjusted Amount Payable 34.56 |
================================================== ===============+
CASH 44
Change Due:
================================================== ================
THANK YOU and HAVE A NICE DAY
Press any key to continue

Originally Posted by Salem

Presumably because you don't do

change_due = some_expression_involving_cash_and_amount_due;

i changed...the out come like this..

Enter Number Of Combo Set : 4
Enter Discount Voucher (RM) : 2
Good Day and Welcome To KLFC Sdn.BhdR E C E I P T
+-------------------------+------------------+-------------------+
+ Description | Rate | Amount(RM) |
+-------------------------+------------------+-------------------+
+ COMBO SET * 4 | 7.88 | 31.52 |
+ Goverment Tax | 6% | 1.89 |
+ Service Tax | 10% | 3.15 |
+-------------------------+------------------+-------------------+
+ S U B T O T A L | 36.56 |
+============================================+==== ===============|
+ Discount Vouvher (RM) 0.00 +
+ -------- |
+ Amount Payable 34.56 |
+ ======== |
+ Adjusted Amount Payable 34.56 |
================================================== ===============+
CASH 44
Change Due:
================================================== ================
THANK YOU and HAVE A NICE DAY
Press any key to continue

So show us what you did to the code.

And don't forget, you need a format conversion in the print statement as well.

Originally Posted by Salem

So show us what you did to the code.

And don't forget, you need a format conversion in the print statement as well.

what did you mean?

Code:

printf(" Change Due:\n",change_due);

Do you expect this to print a number? Why?

Originally Posted by tabstop

Code:

printf(" Change Due:\n",change_due);

Do you expect this to print a number? Why?

ya..>.<...because above the statement also use this way to print out..anything wrong with it?

Originally Posted by tokipatrick

ya..>.<...because above the statement also use this way to print out..anything wrong with it?

You really really need to learn to read a little better. Compare that statement with the "above statement" that works and notice the difference.

Originally Posted by tabstop

You really really need to learn to read a little better. Compare that statement with the "above statement" that works and notice the difference.

i am blur with it..>.<..i am sorry,i still new with C++ language...

Originally Posted by tokipatrick

i am blur with it..>.<..i am sorry,i still new with C++ language...

That's okay, you're not writing C++. Anyway, do you know how to print a number?

Originally Posted by tabstop

That's okay, you're not writing C++. Anyway, do you know how to print a number?

you mean after the calculation?

Originally Posted by tokipatrick

you mean after the calculation?

I mean at all. Do you know how to print any kind of number?

As in,

why do you think this line prints a value,
printf("+ Adjusted Amount Payable %.2lf |\n",a_a_payable);//adjustment amount payable

and this one doesn't
printf(" Change Due:\n",change_due);

Wrong forum? Are you really trying to learn C++?