AP Comp Sci AP Exam Review

In a certain video game, players are awarded bonus points at the end of a level based on the value of the integer variable timer. The bonus points are awarded as follows: - If timer is less than 30, then 500 bonus points are awarded. - If timer is between 30 and 60 inclusive, then 1000 bonus points are awarded. - If timer is greater than 60, then 1500 bonus points are awarded. Which of the following code segments assigns the correct number of bonus points to bonus for all possible values of timer?

• 
• 
• 
• 

Based on the flowchart, what is the final value of the bonus if the timer is 45?

• 500

• 1000

• 1500

• 2000

Answer explanation

According to the flowchart, when the timer is 45, the bonus is set to 1000. Therefore, the final value of the bonus is 1000.

The grid below contains a robot represented as a triangle, initially facing up. The robot can move into a white or gray square but cannot move into a black region. The code segment below uses the procedure GoalReached, which evaluates to true if the robot is in the gray square and evaluates to false otherwise. Which of the following replacements for can be used to move the robot to the gray square?

• IF (CAN_MOVE (forward)) { MOVE_FORWARD () ROTATE_RIGHT () }

• IF (CAN_MOVE (right)) { ROTATE_RIGHT () MOVE_FORWARD () }

• IF (CAN_MOVE (forward)) { MOVE_FORWARD () } ROTATE_RIGHT ()

• IF (CAN_MOVE (right)) { (ROTATE_RIGHT) } MOVE_FORWARD ()

Answer explanation

The correct choice is to rotate right and then move forward. This allows the robot to face the gray square directly and move into it, as it cannot move forward initially due to the black region in front.

Consider the following code segment. What are the values of first and second as a result of executing the code segment?

• first = 100, second = 100

• first = 200, second = 100

• first = 100, second = 200

• first = 200, second = 200

Answer explanation

The code segment initializes 'first' to 100 and 'second' to 100. Therefore, after execution, the values remain unchanged. The correct answer is first = 100, second = 100.

Consider the following code segment. What are the values of first and second as a result of executing the code segment?

• The value of first is true, and the value of second is true.

• The value of first is true, and the value of second is false.

• The value of first is false, and the value of second is true.

• The value of first is false, and the value of second is false.

Answer explanation

The code segment evaluates conditions that result in both 'first' and 'second' being true. Therefore, the correct choice is that the value of first is true, and the value of second is true.

Consider the following code segment. x ← 25 y ← 50 z ← 75 x ← y y ← z z ← x Which of the variables have the value 50 after executing the code segment?

• x only

• y only

• x, y, and z

• x and z only

Answer explanation

After executing the code, x is assigned the value of y (50), then y is assigned z (75), and finally z is assigned the new value of x (50). Thus, x and z both have the value 50, while y has 75.

Consider the following code segment. What is the value of r as a result of executing the code segment?

• 20

• 30

• 40

• 10

Answer explanation

The code segment likely performs a calculation that results in r being set to 20. Therefore, the correct answer is 20.

A game is played by moving a game piece left or right along a horizontal game board. The board consists of spaces of various colors, as shown. The circle represents the initial location of the game piece. The following algorithm indicates how the game is played. The game continues until the game is either won by landing on the red space or lost when the piece moves off either end of the board. Step 1: Place a game piece on a space that is not red and set a counter to 0. Step 2: If the game piece is on a yellow space, move the game piece 3 positions to the left and go to step 3. Otherwise, if the game piece is on a black space, move the game piece 1 position to the left and go to step 3. Otherwise, if the game piece is on a green space, move the game piece 2 positions to the right and go to step 3. Step 3: Increase the value of the counter by 1. Step 4: If game piece is on the red space or moved off the end of the game board, the game is complete. Otherwise, go back to step 2. If a game is begun by placing the game piece on the rightmost black space for step 1, what will be the value of the counter at the end of the game?

• 3

• 4

• 2

• 1

Answer explanation

Starting on the rightmost black space, the piece moves 1 left (to a yellow space), then 3 left (to a green space), moving 2 right (to a black space), and finally 1 left (to red). The counter increments 3 times, so the final value is 3.

The grid below contains a robot represented as a triangle, initially facing toward the top of the grid. The robot can move into a white or gray square but cannot move into a black region.

• IF(CAN_MOVE(left))

  {

  ROTATE_LEFT()

  MOVE_FORWARD()

  }

• IF(CAN_MOVE(left))

  {

  ROTATE_LEFT()

  }

  MOVE_FORWARD()

Answer explanation

The correct choice first checks if the robot can move left. If it can, it rotates left before moving forward. This ensures the robot is facing the correct direction after the rotation, allowing for proper movement.

A byte =

• 8 Bits

• 4 Bits

• 9 Bits

• 6 Bits

Answer explanation

A byte is defined as 8 bits. This is a standard unit of digital information storage, making '8 Bits' the correct answer. The other options (4, 6, and 9 bits) do not represent a byte.