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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
Prime Number Check
Decide whether a number is prime.
You'll learn
DivisibilityLoop optimization
No solutions yet
Easy
Halve Until One
Count how many halvings bring a number down to 1.
You'll learn
While loopsCounting
No solutions yet
Hard
Count Numbers With Distinct Neighbors
Count range values whose adjacent decimal digits are never equal.
You'll learn
Digit DPCounting ranges
No solutions yet
Easy
Multiplication Grid
Build a full multiplication table.
You'll learn
2D listsRow and column indexes
No solutions yet
Medium
List Primes With a Sieve
Find primes up to a limit by marking composite multiples.
You'll learn
Sieve of EratosthenesBoolean arrays
No solutions yet
Hard
Maximum Project Rewards
Choose nonoverlapping projects to earn the largest total reward.
You'll learn
Weighted schedulingDP with binary search
No solutions yet
Easy
Doubling Grains on a Chessboard
Calculate a square’s grain count and the total on all 64 squares.
You'll learn
Powers of twoBig numbers
No solutions yet
Medium
Recursive Power
Compute a power recursively by halving the exponent.
You'll learn
Halving the exponentDivide and conquer
No solutions yet
Easy
Min and Max Together
Find the smallest and largest value in one pass.
You'll learn
Single passMultiple return values
No solutions yet
Easy
Sum Even Fibonacci Terms
Add the even Fibonacci terms that do not exceed a limit.
You'll learn
Sequence generationFiltering
No solutions yet
Medium
Can We Split Into Two Teams?
Decide whether people can be assigned to two teams so that each listed pair is on opposite teams.
You'll learn
Graph coloringBFS
No solutions yet
Medium
Largest Prime Factor
Find the largest prime that divides a positive integer.
You'll learn
Prime factorizationTrial division
No solutions yet
Hard
Cut a Rectangle Into Squares
Find the fewest straight cuts needed to produce only squares.
You'll learn
2D dynamic programmingOptimization
No solutions yet
Hard
Find Many Patterns in Text
For each requested pattern, decide whether it appears as a contiguous substring anywhere in the shared text.
You'll learn
Substring searchPreprocessing
No solutions yet
Medium
Subtract Digits to Reach Zero
Use as few digit subtractions as possible to reach zero.
You'll learn
Minimum steps DPGreedy choice
No solutions yet
Easy
Roman Numeral Value
Convert a Roman numeral to a number.
You'll learn
Symbol-to-value mapsSubtractive rules
No solutions yet
Medium
Sum of Primes Below a Limit
Add all primes strictly below a limit.
You'll learn
Sieve of EratosthenesSumming primes
No solutions yet
Hard
Minimum Elevator Rides
Group people into as few weight-limited elevator rides as possible.
You'll learn
Bitmask DPSubsets
No solutions yet
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