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Python Coding Challenges

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467 challenges 330 easy 120 medium 17 hard
Dicts & Sets easy

Are two lists the same multiset

Write a function that checks if two lists contain the same elements with the same multiplicities, ignoring order.

multiset dictionary counting
+10 pts 10m
Dicts & Sets easy

Word to Index Map

Create a function that returns a dictionary mapping each unique word to the index of its first occurrence.

dictionary mapping indexing
+10 pts 10m
Dicts & Sets easy

Group names by first letter

Given a list of names, return a dictionary mapping each first letter to all names starting with that letter in original order.

dictionaries strings grouping
+10 pts 10m
Dicts & Sets easy

Keys Sorted by Value Descending

Given a dictionary mapping strings to integers, return a list of keys sorted by value descending, and when values tie, alphabetically ascending.

sorting dictionaries ordering
+8 pts 10m
Dicts & Sets easy

Nested get with dotted path

Implement a function that safely retrieves a value from a deeply nested dictionary using a dot-separated path, returning a default if any key is missing.

dicts nested parsing
+8 pts 10m
Dicts & Sets easy

Anagram Dictionary Groups Lite

Group a list of words into anagrams using a dictionary keyed by sorted characters.

dicts strings anagrams
+10 pts 15m
Dicts & Sets easy

Top k keys by count

Given a dictionary mapping keys to counts, return the top k keys with the highest counts, breaking ties alphabetically.

dictionary sorting frequency
+10 pts 15m
Dicts & Sets easy

Replace keys with a mapping

Write a function that renames keys in a dictionary according to a mapping, with duplicate handling.

dicts mapping transformation
+8 pts 10m
Dicts & Sets easy

Two Sum with Dict

Implement the classic Two Sum problem: return indices of two numbers that add up to a target using a dict.

dictionary pair-sum hash-map
+10 pts 15m
Dicts & Sets easy

Top K Frequent Words

Given a list of words, return the k most frequent words sorted by frequency (descending) and then alphabetically.

dictionary sorting frequency
+10 pts 15m
Dicts & Sets easy

Pair with difference K

Count unordered index pairs with absolute difference exactly K, handling duplicates correctly.

dictionary set counting
+10 pts 15m
Dicts & Sets easy

Count Pairs with Sum

Implement a function that counts the number of distinct pairs in a list summing to a target.

dictionary pair-counting hash-map
+10 pts 15m
Dicts & Sets easy

Ransom Note Builder

Given two strings, determine if the ransom note can be formed from the words in the magazine.

dictionary counting strings
+10 pts 15m

Showing 13 challenges · Dicts & Sets

Dicts & Sets — Python coding challenges

What you will find here

This page lists dicts & sets challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

Challenges vs tutorials and quizzes

Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.