| Topic / Pattern | Codility Lesson | Key Problem / Notes |
|---|---|---|
| Arrays & Prefix Sums | Lesson 2 – Arrays | CyclicRotation, OddOccurrencesInArray, basic prefix sums |
| Counting & Hashing | Lesson 4 – Counting Elements | MissingInteger**, FrogRiverOne, **PermCheck |
| Max Slice / Maximum Subarray Sum | Lesson 3 – Time Complexity | MaxSliceSum (use Kadane’s algorithm) |
| Sorting / Greedy | Lesson 6 – Sorting | Distinct**, Triangle, **MaxProductOfThree |
| Stacks & Queues | Lesson 7 – Stacks and Queues | Brackets**, Fish, **StoneWall |
| Leaders / Majority Element | Lesson 8 – Leader | Dominator**, **EquiLeader |
| Number Theory | Lesson 10 – Prime and Composite Numbers | CountFactors**, Peaks, **Flags |
| Prefix Sums + Hashmaps | Lesson 5 – PrefixSums | GenomicRangeQuery**, **CountDistinctSlices |
| Graph / BFS / DFS | Lesson 9 – Caterpillar Method (for sequences) | Problems with path traversal, sometimes FrogRiverOne variants |