Question

What does this method do?

void mystery()
{
while( !karel.nextToABeeper() )
{
karel.pickBeeper();
}
}

A) Picks one beeper.
B) Clears the corner i.e. picks up all beepers.
C) Errors out.
D) Does nothing.

Answer 1

The method has a logical error and does nothing because it tries to pick a beeper where there is none, due to the condition of the while loop.

Step-by-step explanation:

The method in question contains a loop that continues to execute as long as a certain condition is met. This condition is that the robotic object karel is not next to a beeper. Inside the loop, there is an action for karel to pick up a beeper. However, due to the condition checked in the while loop, this method has a logical error. The method will enter the loop only if karel is not next to a beeper, but the first action inside the loop is to pick up a beeper, which cannot be executed if a beeper is not present. Therefore, the correct answer is:

D) Does nothing.

Because the robot will enter the loop only if it's not next to a beeper, yet it immediately tries to pick up a beeper, which it cannot do as per the while loop's condition. Thus, the method will not execute any code and will not pick up any beepers.