Does 

    while ( attempt < 3 && !open )

do what we want?

A good answer might be:

Yes, it means: 

while ( the user has made less than 3 tries AND the lock is NOT open )

Boolean Expression

The Boolean expression 

 attempt < 3 && !open

Should evaluate to true when the user gets the first or another chance, and to false when the user does not get another chance. The table shows how this works:

Number of tries open attempt < 3 !open attempt < 3 && !open Another Chance?
0 false true true true && true true
1 false true true true && true true
1 true true false true && false false
2 false true true true && true true
2 true true false true && false false
3 false ? ? ? && ? ????
3 true ? ? ? && ? ????

The logic in a computer program is often this complicated (or worse!) A chart like this may be necessary to check that the logic is correct.

QUESTION 11:

Fill in the missing entries.

Click Here after you have answered the question