For the wonderfully curious.
See the algorithm.
Build the instinct.
Learn DSA by playing through the logic, then writing the code.
Explore a puzzle. Find the pattern. Turn your discovery into real code. This is interview prep you can get lost in.
Play your first puzzleTry the first puzzle without signing up. Learn at your pace.
Learn by doing.
Remember by discovering.
Two beacons power the gate. Bring their combined energy to the target.
Solid connection: current pair. Gold dashed connections: pairs ruled out by the last move.
Search interval: indices 0 through 4. 5 candidates remain.
sum = values[L] + values[R]if sum == target: return [L + 1, R + 1]if sum < target: L = L + 1if sum > target: R = R - 1
Why does this work?
The stones are sorted. If the sum is too large, even the smallest remaining left stone cannot work with R. Discard R. If too small, even the largest right stone cannot work with L. Discard L. Each safe move preserves all possible answers.
See it. Reason it out. Code it.
One idea, three ways to learn.
Make a move. See what changes.
Understand why the pattern works.
Write code. Prove it with real tests.
Choose where to begin
A clear path from first principles to interview patterns.
Start free. Your first quests let you try the method before choosing lifetime access.
Follow PlayDSA
Short DSA reels with Riya and Aman. Patterns, interview tips and the occasional bad day.
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Other apps from the team behind PlayDSA.
