APCSP Algorithms and Programming 4

Question 1

Which of the following best explains why binary search requires a sorted list?

Accepted Answer

Binary search divides the list in half and discards the half that cannot contain the target, which only works if elements are ordered

Answer

Binary search relies on comparing the middle element to the target and eliminating half the list; this only works correctly when the list is sorted.

Question 2

A programmer wants to repeat a block of code exactly 5 times. Which control structure is most appropriate?

Accepted Answer

REPEAT 5 TIMES loop

Answer

A REPEAT N TIMES loop (or equivalent counted loop) is designed for executing a block a fixed, known number of times.

Question 3

What is the primary purpose of a flowchart in algorithm design?

Accepted Answer

To visually represent the steps and decision points of an algorithm

Answer

Flowcharts use shapes and arrows to visually depict the sequence of steps, branches, and loops in an algorithm before coding begins.

Question 4

Which of the following scenarios best illustrates the benefit of procedural abstraction?

Accepted Answer

Defining a 'calculateTax' procedure once and calling it in multiple places throughout the program

Answer

Procedural abstraction lets you define a procedure once and reuse it anywhere, reducing redundancy and making code easier to maintain.

Question 5

What distinguishes a runtime error from a logic error?

Accepted Answer

Runtime errors cause the program to crash during execution; logic errors produce incorrect results without crashing

Answer

A runtime error halts execution (e.g., dividing by zero), while a logic error allows the program to run but produces wrong output.

(APCSP) AP Computer Science Principles Practice Test