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I like to use couple of constant in comination with an variable to
change the name of the constant.

The further text show my vainly try:

#define KONST1 13 /*Konstanten festlegen*/
#define KONST2 7
#define KONST2 47

main() {

int c = getchar(), i; /*Variablen definieren und
initialisieren*/
for (i = 1, i <= 3, i++) { /*Einfügen von ASCii Zeichen*/
putchar(c+KONSTi);
c = getchar();
}
}

I am a newbie in C and I hope this question is not to nasty.

Have thanks for your kindly support!

Zottel wrote:
>
> I like to use couple of constant in comination with an variable to
> change the name of the constant.
>
> The further text show my vainly try:
>
> #define KONST1 13 /*Konstanten festlegen*/
> #define KONST2 7
> #define KONST2 47
>
You shouldn't redefine a macro without undefining it first.

> main() {

main returns int.

>
> int c = getchar(), i; /*Variablen definieren und
> initialisieren*/

Bad style, don't mix variable assignment and declarations on the same
line. It's often recommended to keep to one declaration per line.

> for (i = 1, i <= 3, i++) { /*Einfügen von ASCii Zeichen*/

The commas should be semicolons.

> putchar(c+KONSTi);

No, you can't do this. Maybe you want to define KONST as an array?

--
Ian Collins.

Zottel wrote:
>
> I like to use couple of constant in comination with an variable to
> change the name of the constant.
>
> The further text show my vainly try:
>
> #define KONST1 13 /*Konstanten festlegen*/
> #define KONST2 7
> #define KONST2 47

illegal. KONST2 is already defined.

--
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Joyeux Noel, Bonne Annee.
Chuck F (cbfalconer at maineline dot net)
<http://cbfalconer.home.att.net>


--
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> > #define KONST1 13 /*Konstanten festlegen*/
> > #define KONST2 7
> > #define KONST2 47
>
> illegal. KONST2 is already defined.
>

Sorry a mistake it should be
#define KONST1 13 /*Konstanten festlegen*/
#define KONST2 7
#define KONST3 47

> > for (i = 1; i <= 3; i++) { /*Einfügen von ASCii Zeichen*/
>
> The commas should be semicolons.
>
> > putchar(c+KONSTi);
>
> No, you can't do this. Maybe you want to define KONST as an array?
>

Hi Ian,
Have thanks for your comment.

How I have to wrote it, if I like to define the KONST as an array?
It should have 2 to 255 fields and the value of each field should be
determined.

CBFalconer said:

> Zottel wrote:
>>
>> I like to use couple of constant in comination with an variable to
>> change the name of the constant.
>>
>> The further text show my vainly try:
>>
>> #define KONST1 13 /*Konstanten festlegen*/
>> #define KONST2 7
>> #define KONST2 47
>
> illegal. KONST2 is already defined.

That isn't why it's illegal. It's illegal because KONST2 is already defined
*differently*. See 3.8.3 (Macro replacement) or the C99 equivalent.

Incidentally, by "illegal" at this point, I simply mean that it's a
constraint violation.

--
Richard Heathfield <http://www.cpax.org.uk>
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999

Zottel wrote:
>>> for (i = 1; i <= 3; i++) { /*Einfügen von ASCii Zeichen*/
>> The commas should be semicolons.
>>
>>> putchar(c+KONSTi);
>> No, you can't do this. Maybe you want to define KONST as an array?
>>
>
> Hi Ian,
> Have thanks for your comment.
>
> How I have to wrote it, if I like to define the KONST as an array?
> It should have 2 to 255 fields and the value of each field should be
> determined.
>
Richard Heathfield just posted what I was typing!

--
Ian Collins.

Zottel said:

>
>
> I like to use couple of constant in comination with an variable to
> change the name of the constant.
>
> The further text show my vainly try:
>
> #define KONST1 13 /*Konstanten festlegen*/
> #define KONST2 7
> #define KONST2 47
>
> main() {
>
> int c = getchar(), i; /*Variablen definieren und
> initialisieren*/
> for (i = 1, i <= 3, i++) { /*Einfügen von ASCii Zeichen*/

You meant <, not <=, and you meant semicolons ; ; not commas , ,

> putchar(c+KONSTi);
> c = getchar();
> }
> }
>
> I am a newbie in C and I hope this question is not to nasty.

For C to be able to do this, the implementation would have to be able to
maintain a symbol table at runtime, and few implementations do that (I
would guess that a C interpreter might, but most C implementations are
compilers).

Instead, I recommend that you use an array. For example:

#include <stdio.h>

int main(void)
{
int konst[] = { 13, 7, 47 };
int c = getchar();
int i;
for(i = 0; i < 3; i++)
{
putchar(c + konst[i]);
c = getchar();
}
return 0;
}

--
Richard Heathfield <http://www.cpax.org.uk>
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999

Hi Richard,

have thank for your solution by using a vector.

#include <stdio.h>
int main(void)
{
int konst[] = { 13, 7, 47 };
int c = getchar();
int i;
for(i = 0; i < 3; i++)
{
putchar(c + konst[i]);
c = getchar();
}
return 0;
}


I have thought about this solution too.

But I like to find a solution with a constant like ..

#define KONST1
.....
#define KONST255

If there is now possibility, I would do it like your suggestion.

Zottel wrote:
> Hi Richard,
>
> have thank for your solution by using a vector.
>
>
> I have thought about this solution too.
>
> But I like to find a solution with a constant like ..
>
> #define KONST1
> .....
> #define KONST255
>
> If there is now possibility, I would do it like your suggestion.

Why? An array is the appropriate solution.

You could initialise the array thus:

int konst[] = { KONST1, KONST2, KONST3 };

--
Ian Collins.