Re: A question about '=='' in C++!

On 21 Sep, 07:15, "Guofu Chen" <gc...@[EMAIL PROTECTED]
> wrote:
> Can anyone tell me the different between
> (1)
> int i, j;
> i = j ==1;
> cout << i;
> cout << j;
>
> and
> (2)
> int i, j;
> i = j = 1;
> cout << i;
> cout << j;
>
> Why the result of  (1) is
>
> 0 0
>
> while the result of (2) is
>
> 1 1
>
> Thanks!
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i = j == 1 : this gives i the value of j and tests if i and j equal to
1 (and they don't because you must have initialized j with 0 before)

i = j = 1 : now this gives i the value of j, and j gets the value of
1, so they all equal with one, no matter what value they used to have.

As a conclusion, "=" gives a value (a = 2; a gets the value 2) and
"==" is a logical operator, compares two values (1 == 2 will return
false).

There are plenty of resources out there to learn all of these ;)
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comp.lang.c.moderated - moderation address: clcm@[EMAIL PROTECTED]
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