CSP Unit 1 Review

Multiple Choice

1. The figure below shows four grids, each containing a robot represented as a triangle. The robot cannot move to a black square or move beyond the edge of the grid. Which of the following algorithms will allow the robot to make a single circuit around the rectangular region of black squares, finishing in the exact location and direction that it started in each of the four grids?

• Step 1: Keep moving forward, one square at a time, until the square to the right of the robot is black.

  Step 2: Turn right and move one square forward.

  Step 3: Repeat steps 1 and 2 three more times.

• Step 1: Keep moving forward, one square at a time, until the square to the right of the robot is no longer black.

  Step 2: Turn right and move one square forward.

  Step 3: Repeat steps 1 and 2 three more times.

• Step 1: Move forward three squares.

  Step 2: Turn right and move one square forward.

  Step 3: If the square to the right of the robot is black, repeat steps 1 and 2.

• Step 1: Move forward three squares.

  Step 2: Turn right and move one square forward.

  Step 3: If the square to the right of the robot is not black, repeat steps 1 and 2.

Two algorithms are used to find the smallest number in a list:

- Algorithm X: Compare each number in the list one by one until the smallest is found.

- Algorithm Y: Divide the list into pairs, remove the larger number, and repeat until one number remains.

Which is true for a list of 64 numbers?

• Algorithm X is faster

• Algorithm Y is faster

• Both are equally fast

• It depends on the numbers

Which factor most strongly affects the efficiency of an algorithm?

• The computer's internet speed

• The number of times instructions repeat

• How easy the steps are to read

• The appearance of the pseudocode

Which of the following is written in low-level machine language?

• print("Hello World")

• MOVE_FORWARD

• 01001001 01001110

• if x > 5 then y = y + 1

A city wants to count how many people ride the subway each day. Which plan is most scalable?

• Have one person count at every station.

• Hire 100 people to stand inside trains and count.

• Use digital turnstiles that record entries automatically.

• Estimate based on the number of trains running.

Using a Caesar cipher with a shift of +5, encode the message: data rules.

• ifyf wzqjx

• efwf vxszn

• ifyf wzumn

• czsz qtkcz

The following grid contains a robot represented as a triangle, which is initially in the bottom-left square of the grid and facing the top of the grid. The robot can move into a white or a gray square but cannot move into a black region.

The following code segment implements an algorithm that moves the robot from its initial position to the gray square and facing the top of the grid.

When the robot reaches the gray square, it turns around and faces the bottom of the grid. Which of the following changes, if any, should be made to the code segment to move the robot back to its original position in the bottom-left square of the grid and facing toward the bottom of the grid?

• Interchange the 

  ROTATE_RIGHT 

  and the 

  ROTATE_LEFT 

  blocks.

• Replace 

  ROTATE_RIGHT 

  with 

  ROTATE_LEFT.

• Replace 

  ROTATE_LEFT 

  with 

  ROTATE_RIGHT.

• No change is needed; the algorithm is correct as is.

Which of the following is an example of algorithmic bias?

• A program crashing due to a missing semicolon

• A hiring algorithm preferring certain genders in data

• A phone battery draining too quickly

• A website taking too long to load

The set of instructions a computer follows to complete a task is called:

• A process

• An algorithm

• An abstraction

• A data type

What type of control structure is shown in a flowchart with a diamond-shaped symbol?

• Iteration

• Selection

• Sequence

• Sorting