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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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Easy
Min and Max Together
Find the smallest and largest value in one pass.
You'll learn
Single passMultiple return values
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
Roman Numeral Value
Convert a Roman numeral to a number.
You'll learn
Symbol-to-value mapsSubtractive rules
No solutions yet
Easy
Character Frequency
Count how often each character appears.
You'll learn
Frequency tablesCounting
No solutions yet
Easy
First Unique Character
Find the first character that appears only once.
You'll learn
Hash mapsCounting
No solutions yet
Easy
Simple Interest
Find the total amount after simple interest.
You'll learn
PercentagesWord problems
No solutions yet
Medium
Readability Grade
Estimate the school grade needed to read a text.
You'll learn
Text analysisFormulas
No solutions yet
Easy
Missing Number
Find the one number missing from 0..n.
You'll learn
Arithmetic seriesSum difference trick
No solutions yet
Easy
Least Common Multiple
Find the smallest positive number divisible by both values.
You'll learn
GCD and LCMNumber theory
No solutions yet
Easy
Power of Two
Check whether a number is a power of two.
You'll learn
Bit manipulationDivision
No solutions yet
Easy
Password Rules Check
Check a password against simple strength rules.
You'll learn
ValidationBoolean flags
No solutions yet
Easy
Palindrome Number
Check whether a number reads the same backwards.
You'll learn
Digit reversalComparisons
No solutions yet
Easy
Remove Duplicates
Keep only the first occurrence of each value.
You'll learn
Seen-value trackingOrder preservation
No solutions yet
Easy
Greatest Common Divisor
Find the largest number that divides both values.
You'll learn
Euclid's algorithmModulo
No solutions yet
Easy
Armstrong Number
Check whether a number equals the sum of its digits raised to the digit count.
You'll learn
Digit extractionPowers
No solutions yet
Easy
Every Other Character
Keep the characters at even positions.
You'll learn
String indexingSteps
No solutions yet
Easy
Sum of Odd Numbers
Add every odd number up to a limit.
You'll learn
For loopsAccumulators
No solutions yet
Easy
Power by Repeated Multiplication
Raise a number to a power with a loop.
You'll learn
Running productZero exponent
No solutions yet
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