National Instruments Interview Experience | Set 1 (Written Test)
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Hi, Recently i have taken written test from "National Instruments", Please check the following questions. Question 1) Brand, Coop and Murph are scientists and are conducti...
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Hi, Recently i have taken written test from "National Instruments", Please check the following questions. Question 1) Brand, Coop and Murph are scientists and are conducting n distinct experiments of various difficulties. All three want to do the experiments in the order of the difficulty of the experiment but there's a catch. They are currently in different time dimensions but are connected by one thing - gravity! If at least two of them end up doing the experiment in the same order then due to gravitational anomaly all the experiment will fail. Now given the number n and a list of difficulties di for each experiment, is there a way to order the experiments such that: All 3 do the experiments in the order of difficulty from least difficult (denote by a lesser difficulty value) to most difficult. The order of these experiments should be unique i.e no two scientists can do the experiments in the same order.
Input: 1 <= n <=2000, 1 <= di <=2000 Output: YES or NO Question 2) Skynet has grown to become the dominant force on earth and has almost completely wiped out the human race. Skynet has been building robots ever since it's inception and has been updating it's models every year while making them better. Skynet wants to annihilate humanity completely. It plans to remove one last band of humans lead by John Connor. Skynet thinks it can destroy these humans using only two of it's robots. But Skynet doesn't want to send two robots with the same model number lest John Connor finds out a weakness in that model and easily destroy both of them. Skynet has at its disposal N robots and to save space Skynet has stored information about pairs of robots belonging to the same model. If it doesn't have any info stored for a particular robot then it is implied that the robot is the only one in that model. Given these constraints, in how many ways can Skynet pick two robots to destroy John Connor and his rag tag group of humans. Inputs N - Total number of robots. Each robot is assigned a number from 0 to N-1 P - Number of pairs for which Skynet has information This is followed by P pairs. Each pair has two numbers P1 and P2 each where 0<=P1<=N-1 and 0<=P2<=N-1 and P1 != P2 Output Number of ways in which Skynet can select 2 robots such that both the robots are different models.
Example Input: 4 2 0 1 2 3 Example Output: 4 Explanation: Here robots 0 and 1 are of one model, say model A. And 2 and 3 are of another model, say B. Therefore the total number of possibilities of picking 2 robots such that no two robots are of the same model are - (0, 2), (0, 3), (1, 2) and (1, 3) = 4
About This Question
This is a reported interview question from a national instruments interview for a swe role (intern level) reported in 2023.
It covers the following topics: Ml .
Difficulty rating: Hard
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About National Instruments Interview Reports
This question was reported by a candidate who interviewed at National Instruments. LeakCode aggregates interview reports from 10+ sources, including 1Point3Acres, Glassdoor, LeetCode Discuss, Blind, Reddit, Indeed, and Nowcoder. Each report is translated where necessary, deduplicated against existing entries, and tagged by company, role, round type, and reporting date.
Use this question as one calibration data point, not a memorization target. Companies typically rotate their question pools every 2-4 months; the exact wording of a 2024 question may differ from what you encounter today. The underlying pattern, difficulty level, and follow-up depth at National Instruments are the higher-signal extractions to take from this report.
For broader preparation context, the National Instruments interview process typically includes a recruiter screen, one or two technical phone screens, and a 4-5 round on-site loop covering coding, system design (at L4+ levels), and behavioral. Reports tagged on LeakCode show the round-by-round distribution and typical difficulty calibration. To browse questions filtered by round type and seniority, use the company hub linked above.
How To Practice This Type of Question
Solve similar problems on LeetCode under timed conditions (25-35 minutes per medium difficulty). The goal is pattern recognition: recognize the underlying technique (sliding window, two-pointer, BFS, memoized recursion, etc.) within 60-90 seconds of reading. Strong candidates verbalize their hypothesis out loud before coding, then iterate based on feedback. Weak candidates dive into implementation immediately, lose time on the wrong approach, and run out of time for follow-ups.
Companies update their question pools every 2-4 months. The exact wording of any given question may have been retired by the time you interview. Focus your prep on the pattern, not the specific problem. The patterns that appear in National Instruments reports consistently are the ones worth investing in; one-off niche problems are not.
During Your National Instruments Round
Apply the standard interview round template: clarify requirements (2-3 minutes), state your approach out loud and confirm direction with the interviewer (3-5 minutes), code with narration (15-25 minutes), test with concrete examples including edge cases (5 minutes), discuss optimization or trade-offs if time permits (5 minutes). This template is universally accepted across FAANG and adjacent companies; deviating from it produces weaker interviewer feedback signal.
The single most predictive failure mode in National Instruments reports tagged "no hire": not asking clarifying questions. Interviewers are explicitly trained to weight this. Strong candidates ask 3-5 clarifying questions even on problems that look obvious; weak candidates dive into code immediately. The clarifying-question check is often the first signal recorded in the interviewer's written notes.