LEARNING PATHS · v4.9
Learning tracks
Follow a structured path, practice with the existing Code Lab and review your saved results. Completion requires a verified 100% score.
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Programming Foundations
Start with functions, collections and string processing.
17 challenges
Running TotalsMediumArrays25 minSolve →Deduplicate Preserving OrderMediumArrays25 minSolve →Alphanumeric PalindromeMediumStrings25 minSolve →Word LengthsEasyStrings12 minSolve →Count VowelsEasyStrings12 minSolve →Sum Odd IndicesEasyArrays12 minSolve →Rotate LeftMediumArrays25 minSolve →Array RangeEasyArrays12 minSolve →Count Even ValuesEasyArrays12 minSolve →Absolute DifferenceEasyBasics12 minSolve →Sum Two NumbersEasyBasics5 minSolve →Count Positive ValuesEasyArrays10 minSolve →Reverse Word OrderEasyStrings15 minSolve →Unique Sorted ValuesEasyArrays15 minSolve →First Unique CharacterMediumStrings20 minSolve →Pair Sum IndicesMediumArrays25 minSolve →Run Length EncodingMediumStrings20 minSolve →Interview Algorithms
Build reliable reasoning for technical interviews.
3 challenges
Add Two Numbers (Linked Lists)MediumLinked Lists25 minSolve →Balanced BracketsMediumStack25 minSolve →Maximum Window SumMediumSliding Window30 minSolve →Array Techniques
Practice traversal, rotation, deduplication and prefix sums.
9 challenges
Running TotalsMediumArrays25 minSolve →Deduplicate Preserving OrderMediumArrays25 minSolve →Sum Odd IndicesEasyArrays12 minSolve →Rotate LeftMediumArrays25 minSolve →Array RangeEasyArrays12 minSolve →Count Even ValuesEasyArrays12 minSolve →Count Positive ValuesEasyArrays10 minSolve →Unique Sorted ValuesEasyArrays15 minSolve →Pair Sum IndicesMediumArrays25 minSolve →Text Processing
Build string normalization and parsing skills.
6 challenges
Alphanumeric PalindromeMediumStrings25 minSolve →Word LengthsEasyStrings12 minSolve →Count VowelsEasyStrings12 minSolve →Reverse Word OrderEasyStrings15 minSolve →First Unique CharacterMediumStrings20 minSolve →Run Length EncodingMediumStrings20 minSolve →Developer Utilities
Solve practical utility functions for application development.
8 challenges
Mask Email UsernameMediumDeveloper Skills25 minSolve →Pagination Chunk CountMediumDeveloper Skills25 minSolve →Inventory TotalEasyDeveloper Skills12 minSolve →Normalize UsernameMediumDeveloper Skills25 minSolve →Clamp ValueEasyDeveloper Skills12 minSolve →Normalize Pagination ParametersEasyDeveloper Skills15 minSolve →Classify HTTP Response CodesEasyDeveloper Skills12 minSolve →Calculate Retry BackoffMediumDeveloper Skills20 minSolve →