Built for off-campus prep

Crack the pattern.
Not the problem.

Ratlo turns 2,000 scattered DSA and placement questions into the 50 patterns that actually matter — built for TCS NQT, HackWithInfy, and India’s off-campus drives.

Start practicing free

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Trusted by students placed at

Three ways to practice

Pick your path. We handle the rest.

Whether you’re prepping for a specific company, drilling a weak pattern, or racing a placement deadline — start exactly where you are.

By Company

Walk into your interview knowing exactly what they ask. Real question sets mapped to each company's actual hiring pattern.

TCSInfosysWiproAccenture

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By Pattern

Stop grinding 2,000 random problems. Master the 50 core patterns that unlock everything else — sliding window, DP, graphs, and more.

Sliding WindowTwo PointersDPGraphs

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By Competitive Exam

Deadline-driven prep. Timed, exam-shaped question banks that mirror the real test — so there are no surprises on the day.

TCS NQTHackWithInfyCoCubeseLitmus

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SYSTEM DESIGN

Design systems that scale.

Go beyond DSA. Learn to architect real systems — from URL shorteners to news feeds — the way senior interviews actually test.

Foundations

Load Balancing & Routing

Distribute incoming traffic across server instances. Learn how Layer 4 and Layer 7 load balancers route queries, manage sessions, and ensure high system availability under sudden traffic surges.

Round-Robin, Least Connections, and Consistent Hashing algorithms.
Active-passive failovers and dynamic health probe checks.

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Building Blocks

Caching Strategies

Reduce database load and improve response times by orders of magnitude. Master cache-aside, write-through, and CDN caching to serve global users instantly.