First Missing Positive Test

The "First Missing Positive" challenge is a classic algorithmic problem used to assess a candidate's ability to design efficient solutions under strict time and space constraints. It tests their understanding of array manipulation, in-place algorithm

Available in

  • English

Summarize this test and see how it helps assess top talent with:

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2 Skills measured

  • Array
  • Hash Table

Test Type

Coding Test

Duration

29 mins

Level

Advanced

Questions

1

Use of First Missing Positive Test

You are given an unsorted integer array nums. Your task is to find the smallest positive integer that does not appear in the array.

  • Your solution must run in O(n) time.
  • It must use O(1) auxiliary space (excluding the input).

This problem requires thoughtful use of indexing and in-place data rearrangement to track existing positive integers efficiently.

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Recruiter efficiency

6x

Recruiter efficiency

Decrease in time to hire

55%

Decrease in time to hire

Candidate satisfaction

94%

Candidate satisfaction

Subject Matter Expert Test

The First Missing Positive Subject Matter Expert

Testlify’s skill tests are designed by experienced SMEs (subject matter experts). We evaluate these experts based on specific metrics such as expertise, capability, and their market reputation. Prior to being published, each skill test is peer-reviewed by other experts and then calibrated based on insights derived from a significant number of test-takers who are well-versed in that skill area. Our inherent feedback systems and built-in algorithms enable our SMEs to refine our tests continually.

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Elevate your recruitment process with Testlify, the finest talent assessment tool. With a diverse test library boasting 3000+ tests, and features such as custom questions, typing test, live coding challenges, Google Suite questions, and psychometric tests, finding the perfect candidate is effortless. Enjoy seamless ATS integrations, white-label features, and multilingual support, all in one platform. Simplify candidate skill evaluation and make informed hiring decisions with Testlify.

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