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Python coding challenges
226 challenges you can solve in Python, from first loops to graphs, dynamic programming and machine learning. Write your code in the browser, run the tests instantly and get an AI review.
Easy · 134 Medium · 68 Hard · 24
Skills you'll practise: CountingDigit extractionString splitting2D listsArithmeticFormulasListsLoopsConditionsDivisibilityFloating pointGradient descent
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- 226
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All challenges
Search by topic, language, or difficulty.
Easy
Pangram Check
A pangram contains every English letter at least once.
You'll learn
Letter setsCase normalization
No solutions yet
Easy
Reverse a String
Return the characters of a string in reverse order.
You'll learn
Reverse iterationSlicing
No solutions yet
Easy
Cart Total With Discount
Total a shopping cart and apply a discount above a threshold.
You'll learn
ListsDiscount rules
No solutions yet
Easy
Anagram Check
Check whether two phrases use the same letters.
You'll learn
SortingFrequency counts
No solutions yet
Easy
Initials From a Name
Build uppercase initials from a full name.
You'll learn
String splittingUppercase
No solutions yet
Easy
Largest of Three
Pick the largest of three numbers without a built-in max.
You'll learn
ComparisonsCombining conditions
No solutions yet
Easy
Replace Spaces With Dashes
Turn spaces into dashes to make a URL-style slug.
You'll learn
String buildingCharacter replacement
No solutions yet
Easy
Count Uppercase Letters
Count the capital letters in a text.
You'll learn
Character checksCounting
No solutions yet
Easy
First Negative Index
Find where the first negative number appears.
You'll learn
Linear searchEarly return
No solutions yet
Easy
Count Positive Numbers
Count the values greater than zero in a list.
You'll learn
ListsCounting
No solutions yet
Easy
Median of a List
Find the middle value of a list after sorting.
You'll learn
SortingStatistics
No solutions yet
Easy
Odd, Even, or Neither
Classify a number by whether it is an odd integer, an even integer, or neither.
You'll learn
ModuloConditions
No solutions yet
Easy
Count Vowels
Count the vowels in a piece of text.
You'll learn
Character checksSet membership
No solutions yet
Easy
Hamming Distance
Compare two DNA strings position by position and count the differences.
You'll learn
String comparisonCounting
No solutions yet
Medium
A* Search on a Weighted Grid
Find the cheapest path across a grid of terrain costs with A*, the search algorithm behind game and robot pathfinding.
You'll learn
A* searchHeuristics
No solutions yet
Medium
Value Iteration
Compute how valuable each state of a Markov decision process is by repeatedly applying the Bellman optimality update.
You'll learn
Bellman equationMDPs
No solutions yet
Easy
Above-Average Values
Keep the values that are greater than the average.
You'll learn
Two passesFiltering
No solutions yet
Easy
Fizz Buzz
Build a sequence using divisibility by 3 and 5.
You'll learn
ConditionsDivisibility
No solutions yet
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