MOCK TEST , Qs. 7

[Ranjit John]

Answer key for Qs. 7 is last option which says

IF ( (A and B) = = FALSE and (A or B) = = TRUE {

                            - - - - - - - - - - - - -- - - - - - -- - - - -- - - 

}

Dont understand the logic asking  BOTH A & B to be FALSE (ie., A should be False and B should be False) and Any of it (A or B) to be True. 

How is it possible  to execute the code where first part ask to ensure both variables should be FALSE and other part asking to ensure any of it to be TRUE ??

It should be If (A == True and B==False) or (A==False and B==True){

                           return (True)

                       }

Please help to understand the answer key.

Since other options donot match at all, i selected last option without checking it and it turned out to be correct. But still confusion remain as it is. 

With regards,

Ranjit John

[Anand Iyer]

Ranjit,

this is a usage that I'm not sure has been dealt with within the course lectures.  But, the usage is valid.

if A == True can be written as if A.  Similarly if B == True can be written as if B.

Thus, the statement if (A and B) == False is interpreted as if ((A == True) and (B == True)) == False

and, the statement if (A or B) == True is interpreted as if ((A == True) or (B == True)) == True

 

Now, look at the attached picture, you should get an idea...

I'm hoping this will clarify your question...

[Reshmi Ranjit]

Thank you Very much for the clarification. 

[Ranjit John]

Thanks a lot Anand.

With regards,

Ranjit John

On Sat, 14 Nov 2020, 15:54 Anand Iyer, <anandd...@gmail.com> wrote:

[Brajesh Kedia]

I find the image for what we can also say "Truth Table" by Anand is wrong... (Check A and B table)

The idea of A and B CONJUNCTION operator is purely based on logic that both have to be true for result to be true.   (Any one false then whole result is false)

The idea of A OR B DISJUNCTION operator is stating the logic, I am fine with any one being true, if both too, i am fine i.e., true..   (If both false that's False as result)

Conclusion - Since, We want Same year or Same Genre but not both hence we are saying we want either A and B = false ,AND, either A or B be True But if A or B be True means A and B is also True but we don't want that...

Understanding THIS last line AGAIN... IN TERMS OF VENN DIAGRAM... We want the common A and B be removed and A and B seperately so we want A and B = false and A or B = true

Point to note - between both conjunction and disjunction operator there is AND than it's fine otherwise we shall conclude in hanging way and get A and B common too.

[rahul agarwalla]

How about considering it binary way:

True=1, False = 0

A and B = A X B, in that case if any one of them is false the result will be FALSE and condition A and B == FALSE will become true.

Parallely A or B = A + B, in that case if any one is true result will be true and the condition A or B == TRUE will be become true

For example A = TRUE (1) and B = TRUE ( 1) ==> A X B =1 and condition that A and B ==FALSE will be BECOME false.

                       A = FALSE (0) and B = TRUE (1) ==> A X B = 0 and condition that A and B == FALSE will become TRUW.

So if condiiton if "  IF ( (A and B) = = FALSE and (A or B) = = TRUE )" ===> If (TRUE AND TRUE) which allow the further opertion inside the loop.

If my understanding is more correct.

[Anand Iyer]

@Brajesh,

I guess you didn't try to understand the problem fully, and my answer.  

Read it again.  It's not a truth table for A and B, it's a truth table for (A and B) is False

--

Cheers,

Anand