Choosing data structures for interview problems in Data Structures Theory - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to choose the best data structure for fast lookup.

Data Structures Theory

best_structure = [1]

Drag options to blanks, or click blank then click option'

Ahash table

Blinked list

Carray

Dstack

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing a linked list which requires linear search.

A hash table provides fast lookup by key, usually in constant time.

2fill in blank

medium

Complete the code to select a data structure that maintains order and allows fast insertion.

Data Structures Theory

chosen_structure = [1]

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Alinked list

Bhash set

Carray

Dqueue

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing array which requires shifting elements on insertion.

A linked list maintains order and allows fast insertion and deletion anywhere.

3fill in blank

hard

Fix the error in choosing the data structure for last-in-first-out access.

Data Structures Theory

data_structure = [1]

Drag options to blanks, or click blank then click option'

Abinary tree

Bstack

Chash map

Dqueue

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing queue which is first-in-first-out (FIFO).

A stack follows last-in-first-out (LIFO) order, suitable for this access pattern.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that filters keys starting with 'a'.

Data Structures Theory

{k: v for k, v in data.items() if k.[1]('a') and v [2] 10}

Drag options to blanks, or click blank then click option'

Astartswith

B>

C<

Dendswith

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'endswith' instead of 'startswith'.

Using '<' instead of '>' for filtering values.

Use startswith to check keys starting with 'a' and > to filter values greater than 10.

5fill in blank

hard

Fill all three blanks to create a set comprehension selecting even numbers greater than 5.

Data Structures Theory

{num for num in numbers if num [1] 5 and num [2] 2 == [3]

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A>

B%

C0

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' for comparison.

Checking modulo equals 1 instead of 0.

Filter numbers greater than 5 and check if they are even by using modulo 2 equals 0.