Part (a)

Write the forwardMoveBlocked method that returns true if the robot cannot move in the direction it's facing.

Solution

private boolean forwardMoveBlocked()
{
    if (facingRight)
        return pos == hall.length - 1;
    else
        return pos == 0;
}

Part (b)

Write the move method that decrements the current position's value and moves the robot according to specified rules.

Solution

private void move()
{
    if (hall[pos] > 0)
        hall[pos]--;
    
    if (hall[pos] == 0)
    {
        if (forwardMoveBlocked())
            facingRight = !facingRight;
        else if (facingRight)
            pos++;
        else
            pos--;
    }
}

Part (c)

Write the clearHall method that repeatedly moves the robot until the hall is clear, returning the number of moves.

Solution

public int clearHall()
{
    int count = 0;
    while (!hallIsClear())
    {
        move();
        count++;
    }
    return count;
}

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