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Beginner coding challenges
Practise beginner with 95 coding challenges, from easy to hard. Every challenge runs in your browser with instant tests, an AI review of your code and community solutions to compare.
Easy · 89 Medium · 6
Skills you'll practise: CountingArithmeticDigit extractionFormulasListsString splitting2D listsConditionsDivisibilityLoopsModuloSingle pass
- Python · C++ · C#
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- 226
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All challenges
Search by topic, language, or difficulty.
Easy
Distance Between Points
Compute the straight-line distance between two points.
You'll learn
Pythagorean theoremSquare roots
No solutions yet
Medium
Count Islands
Count groups of connected land cells in a grid.
You'll learn
Flood fillRecursive DFS
No solutions yet
Easy
Count Pairs With a Sum
Count pairs of positions whose values add up to a target.
You'll learn
Pairs of indexesAvoiding double counts
No solutions yet
Medium
Gradebook Top Student
Find the student with the highest average score.
You'll learn
2D listsAverages
No solutions yet
Easy
Number Triangle
Build a triangle of increasing numbers.
You'll learn
Growing rowsCounters across rows
No solutions yet
Easy
Pyramid Rows
Draw a right-aligned pyramid of # blocks.
You'll learn
String patternsPadding
No solutions yet
Medium
Recursive Palindrome
Check a palindrome recursively, ignoring case and punctuation.
You'll learn
Base casesString cleaning
No solutions yet
Easy
Rectangle Perimeter
Compute the perimeter of a rectangle from its sides.
You'll learn
ArithmeticReturn values
Easy
Hollow Square
Draw the outline of a square with * characters.
You'll learn
Edge detectionBuilding strings
No solutions yet
Easy
Days in a Month
Return how many days a month has, including leap years.
You'll learn
Calendar rulesHelper functions
No solutions yet
Easy
Cash: Fewest Coins
Give change with as few U.S. coins as possible.
You'll learn
Greedy algorithmsCoin change
No solutions yet
Medium
Tic-Tac-Toe Winner
Decide the result of a tic-tac-toe board.
You'll learn
Win conditionsDiagonals
No solutions yet
Easy
Fibonacci Number
Return the n-th Fibonacci number.
You'll learn
IterationUpdating two variables
No solutions yet
Easy
Celsius to Fahrenheit
Convert a temperature from Celsius to Fahrenheit.
You'll learn
FormulasOperator precedence
No solutions yet
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
Easy
Multiplication Grid
Build a full multiplication table.
You'll learn
2D listsRow and column indexes
No solutions yet
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