Address is not incrementing?

Question

It is said that,in c,b++; is equal to b=b+1; if this is the fact test++ in my code why generate a compile time error. test+1 is working well but test++ is not working.but why?

#include<stdio.h>
int main(void)
{
   char test[80]="This is a test";
   int a=13;
   for(;a>=0;a--)
  {
        printf("%c",*(test++);
  }
}

Which _compiler time error_? Something like **error: lvalue required as increment operand**. I think it is self-explicative... — LPs, Apr 18 '16 at 15:55
@LPs: Probably something like "expression `test` is not an lvalue". — EOF, Apr 18 '16 at 15:56
Once you read the actual error message, [**this question**](https://stackoverflow.com/questions/3896637/lvalue-required) and its answers will probably be fairly informative. — WhozCraig, Apr 18 '16 at 16:05

alk · Accepted Answer · 2016-04-18T16:05:01.720

1

The ++ and -- operators are not defined for arrays.

v++; would be the same as v = v + 1;. Assumed v was typed an array this would imply assigning to an array, which is not defined.

edited Apr 18 '16 at 16:05

answered Apr 18 '16 at 15:59

alk

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Oh boy, oh boy ... - so what's wrong here, please? *sigh* – alk Apr 18 '16 at 18:55

score 1 · Answer 2 · answered Apr 18 '16 at 16:04

1

char test[80] = "This is a test";
char *p = test;

for(int a = 0; a < 14; a++)
{
    printf("%c", *(p++));
}

answered Apr 18 '16 at 16:04

Mateen Ulhaq

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And how does this answer the question? – alk Apr 18 '16 at 18:24
@alk It provides a possible solution. Other answers cover what's wrong. – Mateen Ulhaq Apr 18 '16 at 18:27
The question is "*but why?*", not "but how?". I do not want to say additionally providing a solution is wrong, but without giving a reason why the initial approach doesn't work, there is missing an essential part. – alk Apr 18 '16 at 18:50

score 1 · Answer 3 · answered Apr 18 '16 at 16:11

1

Well, for one thing, b++ is not the same as b=b+1.
But even if it were -- I think you'll find you get a similar error if you try test = test + 1.

answered Apr 18 '16 at 16:11

Steve Summit

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I feel this would have better suited as a comment. – alk Apr 18 '16 at 18:24

Address is not incrementing?

3 Answers3