Sorting and Searching Quiz

Sorting and Searching: ten questions on algorithms, search conditions, and operation counts. Includes calculations; answers explained.

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For High school students and adults reviewing the topic.

About 11 minutes. 10 questions.

How does it work?

Choose one answer or enter a number as requested, then check it.
Read the explanation before continuing.
Round only the final answer to the precision requested.

What will you get?

See your score and review the reasoning behind each answer.

Question 1A binary search halves an array of 63 items after each unsuccessful midpoint check. What is the maximum number of midpoint comparisons? Enter a whole number.

Enter a number.

Answers within 0.5 of the expected value are accepted.

Question 2One left-to-right bubble-sort pass starts with 5, 2, 4, 1. Each adjacent pair is swapped if its left value is larger, and the next pair uses the updated list. How many swaps occur? Enter a whole number.

Enter a number.

Answers within 0.5 of the expected value are accepted.

Question 3A linear search checks a list of 27 records from the start for a missing key. How many records does it inspect in the worst case? Enter a whole number.

Enter a number.

Answers within 0.5 of the expected value are accepted.

Question 4Within a database, users need fast lookups by surname and by account number while keeping one main record store. What supports both?

A complete rewrite of the stored records before each lookupA shorter representation that removes the lookup fieldsOne physical ordering that is simultaneously ordered by unrelated keysAn index for each of the two lookup keys

Question 5A binary search finds one matching key, but a report needs the earliest match among several duplicates. What must the implementation establish?

The middle matching record as the definition of earliestThe absence of duplicates before returning a resultThe boundary of the matching range toward the startThe final record’s key as a substitute for the first match

Question 6Textbook analysis says comparison sorting needs roughly n log n comparisons in the general worst case. Which scope is essential?

The input keys occupy a small known range suitable for countingThe method learns order by comparing unrestricted keysThe list already follows the final order before processingThe program is required to move each record just once

Question 7Before choosing an algorithm, a programmer wants binary search to locate a record in an array. What condition supports discarding half the candidates?

The array follows the same ordering used by the comparisonsThe record values are distinct even though their order is arbitraryThe array is ordered by a different field from the search keyThe target has appeared in an earlier search of the array

Question 8Records are sorted by a comparison that places a value before itself. Why is that a problem?

The algorithm needs longer strings instead of numeric keysThe algorithm requires all values to appear exactly onceThe comparison must return the record’s storage addressThe ordering rule contradicts the consistency the algorithm relies on

Question 9A one-time lookup is needed in a short unsorted list. Which comparison is useful when selecting a method?

The total time for sorting then searching equal to the search timeThe length of the source code as the operation countThe cost of scanning versus preparing and then searchingThe number of duplicates as a reason to skip inspecting records

Question 10Records are first ordered by arrival time, then sorted by score. Equal-score records must keep their earlier order. Which property is needed?

A stable sort that preserves the order within tiesA reverse sort that puts the largest score firstA partial sort that returns the top scoring recordsAn in-place sort that stores no full copy of the records

Answer every question to see and share your score.

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