answerCell java challenge

Similar to krakatoa, my one line solution is

    return isAsleep ? false : isMorning ? isMom : true;

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Similar to krakatoa

But sleeker. ;)

On the Venn - to anyone who wants to comment - there are 8 possible "sections" to resolve. Now I haven't given it a massive amount of thought, but I'm wondering to what extent a Venn can really help in designing an algorithm or method logic . . . except perhaps for graphically confirming that all cases are covered. But it doesn't look as if it makes a problem easier to resolve.


btw another one : return !isAsleep&&!isMorning||isMom&&!isAsleep?true:false;

isMorning ? isMom : true
reduces to
   !isMorning || isMom
and
   isAsleep ? false : !isMorning || isMom
reduces to
   !isAsleep && (!isMorning || isMom)

also,
  !isMorning?true:false
reduces to
  !isMorning
and
  (isMorning&&isMom?true:!isMorning)
reduces to
  (isMorning&&isMom||!isMorning)
which reduces to
  (!isMorningis||isMom)

In general,
  (boolean expression)?true:false
is the same as just
  (boolean expression)

  !isAsleep&&!isMorning||isMom&&!isAsleep?true:false;
is the same as
  !isAsleep&&!isMorning||isMom&&!isAsleep
and
  (!isAsleep&&!isMorning)||(isMom&&!isAsleep);
distributes to
  !isAsleep&&(!isMorning||isMom);

In general,
  (boolean expression)?true:false
is the same as just
  (boolean expression)

if this is case

then why people tend to write long code like below
public bolean methodA(){
if(condition){

return true;
}
else(condition(){
return false;
}

}
instead wrte as belwo

public bolean methodA(){
return (boolean expression)

}

or as even more short cut to (boolean expression)?true:false

As I've mentioned before, a good way to move toward robust method formulation is to use clearly visible  signposts for your logic - in other words to write in such terms as :

if (a==1){ return true;}
else {return false;}

then everyone, including you, can see immediately what the intention is.

But once you have your logic right, you can sometimes take shorter routes, so in the above you could write :

return a==1;

The Ternary operator is just an inline 'if' statement really, which, like 'if', can also be nested.

I don't know.
The unnecessary clutter seems to make it harder to see what is important.
But in other circumstances, if the statements inside the conditions have side effects,
then it possible that the long code could add clarity.
If there is a possibility that the code could have to be modified to require such statements with side effects,
then it may be useful for the code structure to reflect that, making it easier to imagine the possible variations.
If the code had originally evolved from other code in which it would have made sense to have a lot of extra statements, then the extraneous structure could be just a historical remnant.
In some cases it may be informative to leave remnants of history, or not worth cleaning it up.
But if the history is not important, it could be a distraction to the reader who may be left wondering what other things you might have been thinking of and what you thought might be useful to do with the the extra structure.

public boolean answerCell(boolean isMorning, boolean isMom, boolean isAsleep) {
  int morn,mum,sleeping,sum;
  
  morn = isMorning?-1:1;
  mum = isMom?2:0;
  sleeping = isAsleep?-3:0;
  
  sum = morn+mum+sleeping;
  
  return sum>=1;
  
}

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:)

public boolean answerCell(boolean isMorning, boolean isMom, boolean isAsleep) {
  
if(isAsleep){

return false;
}

 else if(!isMorning){

return true;
}



else{




if(isMom){

return true;
}

else 

return false;



}
  
}

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i wrote as above and passed all tests

this kind of flow charts helping me to understand better at this stage than venn or tru false table..not sure if there are any limitations of flow charts?
MomCall.png

return isAsleep?false:isMorning&&isMom?true:!isMorning?true:false;


    return isAsleep ? false : isMorning ? isMom : true;



return !isAsleep&&(isMom||!isMorning);

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not able to understand clearly above 3 lines?please advise

how do i start constructing above one line solutions beginning my flow chart posted in last post?

 return isAsleep ? false : isMorning ? isMom : true;

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\

if Asleet it true then return false which is fine
if Asleep false then check morning true or false
morning true check mom true or false
if mom true return true which is all fine
what happened to mom fase morning false cases? we do not need to write them or is it by default understood by jvm something??

 return isAsleep ? false : isMorning ? isMom : true;
// more verbosely:
 return
    ( isAsleep )?(
         false
    ):(
       ( isMorning )?(
            isMom
       ):(
             true
       )
    )
 ;
// in other words:
   if( isAsleep ){
         return false;
   }else{
       if( isMorning ){
            return isMom;
       }else{
             return true;
       }
    }
// or more succinctly:
 return !isAsleep&&(!isMorning||isMom);

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return isAsleep ? false : isMorning ? isMom : true;

how to break above to below?

 if( isAsleep ){
         return false;
   }else{
       if( isMorning ){
            return isMom;
       }else{
             return true;
       }
    }

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is there is rule or thumb rule for this?

It follows from the definition of the ?: operator
- and an intention style that always uses braces after an if() and cuddles elses at the same indentation level.

It follows from the definition of the ?: operator
- and an intention style that always uses braces after an if() and cuddles elses at the same indentation level.

i got it

return isAsleep ? false : isMorning ? isMom : true;


how to break above to below?
 if( isAsleep ){
         return false;
   }else{
    //return true//or can result boolean still having one other if else
                                 if(){
                                       }
                                        else{
                                                 }//can be one other if else??
       }
    }


how many levels down we can go like this???

We've been over this "depth" and "nesting" question many times, and it's starting to look like we are repeating ourselves.

You can nest if and else and else if as many times as the Java language will allow. Jim cakalic and mccarl already said that your brain would give up before you reached that level of nesting -so why are you worried about it? If you had a problem of that level of if-else ness, you would be implementing it the wrong way by then.

Not ? But : means we almost reached end of nesting right

You don't reach the end until you have as many : as ?

You don't reach the end until you have as many : as ?

i was not aware of this fact.

Does that mean you thought you could have ? without :

i thought ? could have more than one : which is wrong.

where i can read all about ternary operator at great great detail.

http://lmgtfy.com/?q=java+ternary+operator