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Student beginner coding challenges
Practise student beginner with 28 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 · 27 Medium · 1
Skills you'll practise: CountingModuloSingle passString splittingTracking a maximumTwo pointersAccumulatorsArithmetic seriesArray indexingBit manipulationCapitalizationCharacter checks
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Easy
Cash: Fewest Coins
Give change with as few U.S. coins as possible.
You'll learn
Greedy algorithmsCoin change
No solutions yet
Easy
Fibonacci Number
Return the n-th Fibonacci number.
You'll learn
IterationUpdating two variables
No solutions yet
Easy
Prime Number Check
Decide whether a number is prime.
You'll learn
DivisibilityLoop optimization
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
Medium
Readability Grade
Estimate the school grade needed to read a text.
You'll learn
Text analysisFormulas
No solutions yet
Easy
First Unique Character
Find the first character that appears only once.
You'll learn
Hash mapsCounting
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
Missing Number
Find the one number missing from 0..n.
You'll learn
Arithmetic seriesSum difference trick
No solutions yet
Easy
Palindrome Number
Check whether a number reads the same backwards.
You'll learn
Digit reversalComparisons
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
Remove Duplicates
Keep only the first occurrence of each value.
You'll learn
Seen-value trackingOrder preservation
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
Greatest Common Divisor
Find the largest number that divides both values.
You'll learn
Euclid's algorithmModulo
No solutions yet
Easy
Palindrome String
Check whether text reads the same forwards and backwards.
You'll learn
Two pointersEarly exit
No solutions yet
Easy
Title Case
Capitalize the first letter of every word.
You'll learn
String methodsCapitalization
No solutions yet
Easy
Anagram Check
Check whether two phrases use the same letters.
You'll learn
SortingFrequency counts
No solutions yet
Easy
Reverse a String
Return the characters of a string in reverse order.
You'll learn
Reverse iterationSlicing
No solutions yet
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