Puzzles
You watched it. Now prove it — play each algorithm's strategy by hand. Solving locks the idea into memory in a way watching never can.
🔒 Locked
Guess my number
Apply Binary Search
Learn Binary Search first →
🔒 LockedClose the gap
Apply Two Pointers
Learn Two Pointers first →
🔒 LockedSpread the search
Apply BFS
Learn Breadth-First Search first →
🔒 LockedBeat the scan
Apply Hashing
Learn Hashing (Hash Set) first →
🔒 LockedGo deep
Apply DFS
Learn Depth-First Search first →
🔒 LockedNext out
Apply Stack & Queue
Learn Stack & Queue first →
🔒 LockedFind its place
Apply Insertion Sort
Learn Insertion Sort first →