Thread: having problem with if statement

You simply have a syntax error on this line:

Code:

if(County 65)

You did get it right on this line:

Code:

if(County == 65)

Since you do the same thing on both branches of the if statement, you might as well just write:

Code:

printf("%3.2f", Purchase += (Purchase * TaxRate / 100));

Personally, I would write:

Code:

Purchase += Purchase * TaxRate / 100;
printf("%3.2f", Purchase);

as it is less likely to result in a mistake.

Originally Posted by ninjaman

I thought that adding the decimal value 65 for A 97 for a

Avoid magic numbers. Instead of using 65, use 'A'. Instead of using 97, use 'a'.

Originally Posted by laserlight

Instead of using 65, use 'A'. Instead of using 97, use 'a'.

What makes you suggest it? It is not that user presses 'A' when asked for county. He will have to enter numbered code of the county, I suppose, seeing the code. So why do you suppose this numbered code has anything to do with ASCII?

What makes you suggest it? It is not that user presses 'A' when asked for county. He will have to enter numbered code of the county, I suppose, seeing the code. So why do you suppose this numbered code has anything to do with ASCII?

O_o

would be a letter

the decimal value 65 for A 97 for a

I put in either B or b

I have looked at char

I suppose it could just be coincidence.

Soma

Try dividing by 100.0 instead of 100 I suggest learning about integer division.

Edit: This line implies Purchase is a float/double; but, I think you declared it as int.

Code:

printf("%3.2f", Purchase);

Tim S.

I cant get the switch case working for some reason.

O_o

1): You are consuming, from input, an `int' while you are probably typing 'A'/'a'/'B'/'b' which are not of `int' type leaving the value of `Country' at zero.

2): You have told `printf' that the variable `Purchase' is a `float' which is actually of `int' type.

Soma

What is your current code and how does it not work?

Code:

#include <stdio.h>
int Purchase, TaxRate;
char County;
int main()
{
 printf("AMOUNT OF PURCHASE? ");
 scanf("%i", &Purchase);
 printf("COUNTY? ");
 scanf("%c \n", &County);
 printf("TOTAL BILL: $ ");
 switch(County)
 {
 case 65:
    TaxRate = 7;
    Purchase += (Purchase * TaxRate / 100.0);
    break;
 default:
    TaxRate = 6;
    Purchase += (Purchase * TaxRate / 100.0);
    break;
 }
 printf("%3.2f", (float) Purchase);
}

this is the current code, I have made changes that people have suggested. I type in 15, A for county, and total bill appears as 15.00. when I type anything for county total bill comes up as 15.00.
I don't think the switch case is working, or if its getting to switch case. I think it is bypassing it for some reason.

thanks
simon


I included,
printf("taxrate is %1 \n", TaxRate);
and it prints,
taxrate is 6

so the switch case is working to some extent. I don't think the "County" thing is working. also, the expression purchase += (purchase etc..) this is not working. otherwise the default value would give a different number at output.

ok latest code

Code:

#include <stdio.h>
float Purchase, TaxRate;
char County;
int main()
{
 printf("AMOUNT OF PURCHASE? ");
 scanf("%f", &Purchase);
 printf("COUNTY? ");
 scanf("%c \n", &County);
 switch(County)
 {
 case 65:
    TaxRate = 7;
    break;
 default:
    TaxRate = 6;
    break;
 }
Purchase += (Purchase * TaxRate / 100.0);
 printf("taxrate is %1.0f \n", TaxRate);
 printf("TOTAL BILL: $ ");
 printf("%3.2f", Purchase);
}

this takes and shows input, shows county, shows default taxrate no matter what letter is pressed, shows the correct value of purchase and tax. so the purchase expression is working. the switch case is not.

Your latest code looks like it is on the right track, but I would improve it to:

Code:

#include <stdio.h>

int main(void)
{
    float Purchase, TaxRate;
    char County;
    printf("AMOUNT OF PURCHASE? ");
    scanf("%f", &Purchase);
    printf("COUNTY? ");
    scanf(" %c", &County);
    switch (County)
    {
    case 'A':
        TaxRate = 7;
        break;
    default:
        TaxRate = 6;
        break;
    }
    Purchase += (Purchase * TaxRate / 100.0);
    printf("taxrate is %1.0f\n", TaxRate);
    printf("TOTAL BILL: $ %3.2f\n", Purchase);
    return 0;
}

A few changes to note:

• My indentation for a single level is more than just a space, hence it provides better contrast between indent levels.
• I made the variables into local variables. It does not matter for so trivial a program, but you should get into the habit.
• I use " %c" instead of "%c \n" for the format specification to read into Country. You want to discard the newline left over from the previous scanf, so it makes sense for there to be a leading space.
• I use 'A' instead of 65.
• I used a single printf for the TOTAL BILL printing. This, after all, is partly why we have formatted output. I could have combined it further with the taxrate printing.
• I also used int main(void) instead of int main(). This makes no difference since this is a function definition, not a forward declaration, but you might as well get into the habit.
• I placed a return 0; at the end. This is optional if you are compiling with respect to C99 or later as a special concession to the main function.

Another thing that I could have done is to check the return value of scanf.