P-7.1 How a Coding Round Runs
You can tell which of the three round formats you are sitting, and you have a method for the first ten minutes that works in all three.
A first technical round takes one of three shapes and they reward different things. A written screening test is mostly multiple-choice questions about what a printed function outputs, on a clock that leaves about a minute each. A timed coding test wants working code against cases you cannot see. A live interview wants your reasoning out loud and a working answer second. The depth differs by who is hiring, and this module says so plainly: a services company screens for whether you can read code and write a correct loop, while a product company pushes into the data structures and cost analysis taught in the two modules before this one. Same subjects, different depth, which is why this module is the treatment and not a second copy of them.
Work through these
Name the three round formats, and find out which one your target company runs
A written screening test, a timed coding test with hidden cases, and a live interview are three different games. Most companies describe their own pattern on their own careers pages, and reading it before you prepare saves weeks of the wrong practice.
NPTEL: Complete guide for campus interviews · CourseThe first ten minutes: read it, restate it, ask about the edges, write two examples by hand
Most failed rounds are lost before any code is written, by answering a question nobody asked. Restating the problem and working two small examples on paper exposes the misunderstanding while it still costs nothing to fix.
Write the obvious slow answer first, and say out loud that it is slow
A working answer that runs in quadratic time scores far better than an elegant one that does not run at all. Naming its cost yourself shows you know the difference, which is most of what the round is measuring.
Improve one step at a time, and keep the version that works
The improvement is usually replacing a scan with a lookup, or sorting once so the rest becomes cheap. Changing one thing at a time means you still have something that runs when the clock stops.
Test your own answer on the empty input, the single item, and the repeated value
Hidden test sets are built out of edge cases, and those three catch a large share of them. Running them yourself before you say you are finished is the difference between a pass and a near miss.
Talk while you work, and say where you are unsure
A silent candidate is unreadable to an interviewer who is grading the reasoning as much as the result. Saying where you are stuck is also how you get the hint that unblocks the question.
NPTEL: Complete guide for campus interviews · Course
Sign in to keep your progress.
Free resources
We haven't checked most of these for screen reader use yet.
Links last checked 2 Sept 2026.
Stuck here?
Ask a mentor. A real person answers, and they can see exactly which topic you're on. Usually within a couple of working days.
Checking your session…
Topics shown in module order.