Free Practice Quiz Question List

8 Searching Algorithms Online Quiz Questions

Use this free practice quiz with 20 questions to review 8 Searching Algorithms, test your knowledge, and prepare for your next test or exam.

20 questions

Choose one

1 point

Which data structure generally offers expected $O(1)$ lookup for exact-key searches but does not naturally support ordered queries such as “find the smallest value greater than $x$ ”?

A
Binary search
B
A hash table
C
Linear search
D
A balanced search tree

Choose one

1 point

Which collection is the most suitable for a straightforward iterative binary search because its middle element can be accessed directly by index?

A
An array
B
A singly linked list
C
An unordered set without indexing
D
A stream that can only be read once

Choose one

1 point

Why is $low + (high - low) // 2$ preferred to $(low + high) // 2$ in some fixed-width integer languages?

A
It always produces a floating-point midpoint.
B
It searches both halves simultaneously.
C
It avoids adding the two potentially large indices directly.
D
It guarantees that the target is present.

Choose all

1 point

Which two conditions are required for binary search to provide its usual efficient behavior?

A
The collection is sorted according to the search comparison rule.
B
The collection must contain distinct values.
C
The middle element can be accessed efficiently.
D
The collection must be stored in a linked list.

Choose all

1 point

Which two statements correctly describe the trade-offs involved in sorting data before using binary search?

A
Sorting cost must be included when analyzing the complete process.
B
Maintaining sorted order may increase insertion and deletion costs.
C
Binary search remains valid on unsorted data after one failed comparison.
D
Sorting always makes a single search faster overall.

True or false

1 point

True or false: Under the usual assumption that a target is equally likely to occur at any position, linear search has average-case time $O(n)$ .

A
True
B
False

True or false

1 point

True or false: Recursive binary search typically uses more extra space than iterative binary search because of its call stack.

A
True
B
False

Written response

1 point

In a sorted collection containing duplicate target values, what result does a modified binary search return when it continues left after each match?

Written response

1 point

For approximately one million sorted array elements, about how many halving steps does binary search need in the worst case?

Fill in the blank

1 point

To find the first occurrence of a target after a match is found, the algorithm continues searching to the .

Fill in the blank

1 point

Binary search requires the collection to be arranged in according to the comparison rule used by the search.

Open ended

1 point

A program repeatedly searches a small collection whose elements change frequently, and the collection is not kept sorted. Which search strategy should be chosen, and why? Explain the relevant search and maintenance costs.

Choose one

1 point

Which statement is the loop invariant used to justify the correctness of iterative binary search?

A
Every element outside the range has already been returned as a match.
B
If the target occurs, it occurs within the inclusive range from low through high.
C
The target is equally likely to occur at every index in the range.
D
The range always contains exactly half of the original array.

Choose one

1 point

Why can a straightforward binary-search strategy be inefficient on a sorted linked list?

A
Repeatedly locating middle nodes requires traversal.
B
Linked lists cannot contain sorted values.
C
Linear search is impossible on linked lists.
D
A linked list always changes its values during a search.

Choose one

1 point

Why is the midpoint expression low + (high - low) // 2 preferred to (low + high) // 2 in some implementations of binary search?

A
It guarantees that the target is at the exact middle of the array.
B
It reduces the risk of integer overflow when computing the midpoint.
C
It allows binary search to work on unsorted data.
D
It makes linked-list access constant time.

Choose one

1 point

Which task is not naturally supported by a hash table's expected constant-time exact-key lookup?

A
Finding whether an exact key is present
B
Returning the record associated with an exact key
C
Finding the smallest stored value greater than a given value
D
Testing whether two exact keys are equal

Choose one

1 point

A linear search examines every element and reaches the end without finding the target. What conclusion is justified?

A
The target must be at the first position.
B
The collection must have been sorted first.
C
Every position has been checked and the target is absent.
D
The target is present but has no associated record.

True or false

1 point

True or false: For binary search, an iterative implementation typically uses constant extra space, whereas a recursive implementation typically uses logarithmic call-stack space.

A
True
B
False

Written response

1 point

A sorted array contains approximately one million elements. In the worst case, about how many halving steps does binary search need?

Written response

1 point

What is the standard algorithmic term for a property that remains true before and after every iteration and is used to prove a search algorithm correct?