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Doubt in Question 6 (KB Book Chapter 4)

 
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Hi,

Here's the question:

Given:
class Titanic {
public static void main(String[] args) {
Boolean bl = true;
boolean b2 = false;
boolean b3 = true;
if((bl & b2) | (b2 & b3) & b3)
System.out.print("alpha ");
if((bl = false) | (b1 & b3) | (bl | b2))
System.out.print("beta "};
}
}
What is the result?
A.beta
B.alpha
C.alpha beta
D.Compilation fails.
E.No output is produced.
F.An exception is thrown at runtime.


I am not completely satisfied with the explanation on the answer. Could you please carefully tell me what exactly is happening at this line?
if((bl = false) | (b1 & b3) | (bl | b2))

Thanks!
 
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----------------------------------------------------------------------

class Titanic {
public static void main(String[] args) {
Boolean bl = true;
boolean b2 = false;
boolean b3 = true;
if((bl & b2) | (b2 & b3) & b3)
System.out.print("alpha ");
if((bl = false) | (b1 & b3) | (bl | b2))
System.out.print("beta "};
}
}
--------------------------------------------------------

In the statement

if((bl = false) | (b1 & b3) | (bl | b2))

at first we are assigning false to boolean variable b1 . thats why now b1 is not 'true' rather it is 'false'..after that (b1 & b3) is just (false & true ) which is finally 'false' similarly (bl | b2) is just (false | false ) i.e false.

final experssion is just like (false|false|false)--> false

hence thats if() block is not executed...

Hope it will help you..
 
With a little knowledge, a cast iron skillet is non-stick and lasts a lifetime.
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