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Why the output of below program is not as expected?

0 votes
536 views 
#include<stdio.h>
main()
{
        int a=10;
        printf("%d\n",a++==a);
}

Output should be 1 but it is coming as 0,
Can anyone please explain?

posted Sep 14, 2017 by anonymous

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Mine is coming as 1 (http://codepad.org/CHaTPyJs )
So it may be compiler dependent behavior, if operation is executed from left to right then answer would come as zero else 1.
commented Sep 14, 2017 by Salil Agrawal

1 Answer

0 votes

Assume, compiler executes statement a++==a from left to right, then
a = 10
a++ becomes 11
so, a++(10) == a(now becomes 11)

answer Sep 15, 2017 by anonymous
Thanks for the answer,
But I don't think, this left to right explanation is right,
Because if this explanation is correct then,
If a++==a is giving o/p 0 then a==a++ should give o/p as 1
commented Sep 15, 2017 by Chirag Gangdev
It's about precedence.++ Is higher precedence than ==. I think you got the ans
commented Oct 12, 2017 by Naveen Kumar
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