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

Guofu Chen 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

Well, I don't know how this C++ question slipped through into clcm,
but since the question could be asked in C just as easily by
replacing the cout stuff with printf...

Certainly you must have read even the most basic C (or C++ in this
case) book, which explains that "=" is assignment and "==" is the
euqality operator?

Consider that "i = j == 1;" is equivalent to "i = (j == 1);".

What do you expect "i = j == 1;" to do?  (Besides invoke undefined
behavior, as j has an indeterminiate value.  Didn't you get any
warnings about using uninitialzied variables?  Or does C++ make
sure to initialize them to zero?)

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>
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