Programming Challenges

Strengthen your problem-solving skills with language-neutral challenges you can solve in Python, C++, or C#. Every submission is checked by automated tests and reviewed by AI.

  • Python · C++ · C#
  • Automated tests
  • AI code review
  • Community solutions
Learning path
150
Challenges
0
Solutions shared
3
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All challenges

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25 challenges
Easy

Every Other Character

Keep the characters at even positions.

BeginnerLearning-pathStrings
No solutions yet
Hard

Word Break

Decide whether text can be split into dictionary words.

AdvancedDynamic-programmingHackathonStrings
No solutions yet
Hard

Minimum Window Substring

Find the shortest piece of text containing all required characters.

AdvancedCompetitive-programmingSliding-windowStrings
No solutions yet
Medium

Recursive Palindrome

Check a palindrome recursively, ignoring case and punctuation.

BeginnerLearning-pathRecursionStrings
No solutions yet
Easy

Count Uppercase Letters

Count the capital letters in a text.

BeginnerLearning-pathStrings
No solutions yet
Medium

Readability Grade

Estimate the school grade needed to read a text.

BeginnerStringsStudent-beginnermath
No solutions yet
Easy

Longest Word

Find the longest word in a sentence.

BeginnerStringsStudent-beginner
No solutions yet
Easy

Count Words

Count the words in a sentence.

BeginnerStringsStudent-beginner
No solutions yet
Easy

Character Frequency

Count how often each character appears.

BeginnerDictionariesStringsStudent-beginner
No solutions yet
Easy

Pangram Check

A pangram contains every English letter at least once.

SetsStrings
No solutions yet
Easy

First Unique Character

Find the first character that appears only once.

BeginnerDictionariesStringsStudent-beginner
No solutions yet
Easy

Reverse a String

Return the characters of a string in reverse order.

BeginnerStringsStudent-beginner
No solutions yet
Easy

Initials From a Name

Build uppercase initials from a full name.

BeginnerLearning-pathStrings
No solutions yet
Easy

Roman Numeral Value

Convert a Roman numeral to a number.

BeginnerLookup-tablesStringsStudent-beginner
No solutions yet
Easy

Title Case

Capitalize the first letter of every word.

BeginnerStringsStudent-beginner
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Easy

Palindrome String

Check whether text reads the same forwards and backwards.

BeginnerStringsStudent-beginner
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.

Pattern-matchingStringsTries
No solutions yet
Easy

Hamming Distance

Compare two DNA strings position by position and count the differences.

SequencesStrings
No solutions yet