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Algorithms you can see — 100% free.

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0-day streakApprentice

0 XP · 0/638 understood

Daily goal 0/1

Prep plan Browse all

Learn the Basics44

Sorting Techniques11

Arrays & Hashing51

Sliding Window20

Binary Search51

Bit Manipulation24

Heap / Priority Queue21

Binary Search Trees21

Depth-First Search25

Breadth-First Search10

OverviewSort, then sweep · overlap ⇔ b.start ≤ a.end
Merge IntervalsSort by start · extend while overlapping
Meeting Rooms IIChronological sweep · peak overlap = rooms
Practice problems
Meeting RoomsSort by start, check each neighbour

Dynamic Programming65

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Intervals

Sort by an endpoint, then sweep for overlaps.

0/ 4 understood · 0%

Walkthroughs: 4
Problems: 4

4 shown

OverviewSort, then sweep · overlap ⇔ b.start ≤ a.endanimatedMedium
Merge IntervalsSort by start · extend while overlappinganimatedMedium
Meeting Rooms IIChronological sweep · peak overlap = roomsanimatedMedium
Practice problems
Meeting RoomsSort by start, check each neighbouranimatedMedium