Free Practice Quiz Question List

8 Testing, Debugging, and Algorithmic Efficiency Online Quiz Questions

Use this free practice quiz with 20 questions to review 8 Testing, Debugging, and Algorithmic Efficiency, test your knowledge, and prepare for your next test or exam.

20 questions

Choose one

1 point

A function accepts scores from 0 through 100 inclusive. Which testing strategy is most likely to reveal an error caused by using < instead of <=?

A
Use only the most common valid input.
B
Test values at and around the input limit.
C
Test only inputs that produce an error.
D
Avoid testing the exact boundary because it is predictable.

Choose all

1 point

Which two outcomes should a robust test for invalid input verify? Select all that apply.

A
The invalid input is detected.
B
The program produces an ordinary result anyway.
C
The program does not silently produce a misleading result.
D
The test uses only valid inputs.

Written response

1 point

What technical term names a defect in a program?

Fill in the blank

1 point

Complete each definition. A states what must be true before an algorithm begins. A states what must be true when it finishes.

True or false

1 point

True or false: Testing can reveal that a program fails, but debugging is the process used to investigate and correct the cause.

A
True
B
False

Choose one

1 point

After fixing a defect, why should the team keep a regression test for it?

A
It replaces all normal test cases.
B
It measures only memory usage.
C
It would fail if the same bug returned.
D
It guarantees that no future bugs are possible.

Choose all

1 point

Which two statements accurately describe reasoning about algorithm correctness? Select all that apply.

A
A loop invariant remains true before and after each loop iteration.
B
A few successful examples prove correctness for every permitted input.
C
Correctness applies only to the most common input category.
D
Correctness requires the required result for every input satisfying the stated conditions.

Written response

1 point

What is the two-word term for a property that remains true before and after each loop iteration?

Choose one

1 point

A binary search examines a sorted list by repeatedly halving the remaining search space. What is its typical running-time growth in terms of the list length n?

A
O(n)
B
O(log n)
C
O(n²)
D
O(1)

Choose one

1 point

The slow duplicate-checking function compares pairs of items using two nested loops. What is its worst-case time complexity?

A
O(n²)
B
O(n)
C
O(log n)
D
O(1)

True or false

1 point

True or false: Replacing the nested-loop duplicate check with a set usually improves the time complexity to $O(n)$ , but requires $O(n)$ additional memory.

A
True
B
False

Open ended

1 point

Consider this function:

\texttt{def count\_positive(values):}

\texttt{ count = 0}

\texttt{ for i in range(1, len(values)):\texttt{}}

\texttt{ if values[i] > 0:\texttt{}}

\texttt{ count += 1}

\texttt{ return count}

Explain why it gives an incorrect result for some valid inputs, identify a minimal revealing test case, and describe a suitable correction. Include how the revealing test should be used after the fix.

Fill in the blank

1 point

Complete the documentation requirement: Binary search requires the input values to be in nondecreasing order.

Choose one

1 point

In the complete problem-solving workflow, what should a programmer do first when approaching a new programming problem?

A
Clarify the specification.
B
Choose a faster data structure immediately.
C
Document the final solution.
D
Run the full test set before defining expected behavior.

Choose one

1 point

A score is valid from 0 through 100 inclusive. Which test set best applies boundary-value testing?

A
Only scores from 1 through 99, because endpoint values are unusual
B
Scores just below, at, and just above both valid boundaries
C
Only randomly selected scores between 0 and 100
D
Only invalid scores below 0

True or false

1 point

True or false: If an algorithm passes several carefully chosen examples, those examples alone prove that the algorithm is correct for every allowed input.

A
True
B
False

Choose one

1 point

A function is intended to count positive values, but it uses for i in range(1, len(values)). On input [4, -1, 2], it returns 1 instead of 2. What is the most likely cause of the failure?

A
Change count = 0 to count = 1
B
Change the condition to values[i] >= 0
C
Start the loop at index 0 or iterate directly over the values
D
Return len(values) after the loop

Written response

1 point

In a linear search, what is the name of the property that remains true before and after each iteration?

Choose one

1 point

An algorithm uses two nested loops, and each loop may process all $n$ items in a list. What is the usual worst-case running time?

A
$O(n)$
B
$O(n^2)$
C
$O(\log n)$
D
$O(1)$

Written response

1 point

What asymptotic time complexity describes a direct calculation whose amount of work does not depend on the input size $n$ ? Enter the constant-time complexity in the form $O(1)$ .