2.3 The door that will not open

The door that will not open

Unit 2: Variables, Decisions, and Input · Lesson 2.3 Boolean Expressions · code exercise, graded

Two questions, one answer. The door opens when you have the key AND the alarm is not going off, which needs both && and !.

What to write

  1. Return true when the player has the key and the alarm is NOT ringing.
  2. Return false in every other case.

Do not write `== true` anywhere. hasKey is already true or false, which is exactly what an expression wants.

Your code

This one prints numbers rather than moving anything, so there is nothing to animate. Press Submit to check it.




What it is checked against


These are the examples you can see. There are also 3 hidden cases with different setups, so printing the answers below as text passes nothing.




Example 1: what we set up


Harness h = new Harness();
System.out.println(h.canOpen(true, false));


What it should print


true






Example 2: what we set up


Harness h = new Harness();
System.out.println(h.canOpen(true, true));


What it should print


false









  

















  
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