Why does value of j not change?

Question

In the following code why does the value of j remains zero even after the statement j=i+10.

#include <stdio.h>
int main()
{
 int i = 10, j = 0;
 if (i || (j=i+10))
   printf("%d",j);// j=0
}

C does [*short-circuit evaluation*](https://en.wikipedia.org/wiki/Short-circuit_evaluation). Something you should have know if you read a book or two. — Some programmer dude, Apr 14 '18 at 13:11
I don't write `c`, but is it because you're using a logical OR operator, and if `i` evaluates to `true` then the `j=i+10` wouldn't get evaluated? — Robert Seaman, Apr 14 '18 at 13:11

Achal · Answer 1 · 2018-04-14T13:32:19.003

4

Why does value of j not change? Because i is non-zero and logical OR (||) properties is that if 1st operand is true don't check 2nd operand.

if ( i    ||  (j=i+10))
     |           |             
    10(True)   not evaluated

edited Apr 14 '18 at 13:32

answered Apr 14 '18 at 13:11

Achal

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ISO9899:1990 is not C standard since ca. 19 years now. Please don't cite outdated versions of standards, unless a question asks for them. – too honest for this site Apr 14 '18 at 13:27

Why does value of j not change?

1 Answers1