Problem 2990. Replace every 3rd element in a vector with 4

Created by Yaz Majeed

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x is a vector of undetermined length

You are to replace every 3rd element with the number 4, example:

x = [11 23 34 43 2 31 6 34 5 45 26 7 78];

output = [11 23 4 43 2 4 6 34 4 45 26 4 78];

Make sure the code accounts for varying vector lengths

Solve

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Last Solution submitted on Dec 08, 2025

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Guillaume on 10 Feb 2015

In view of the recent spate of trivial problems with no test suite to speak of, thanks for making the effort of providing a proper test suite and a slightly less trivial problem.

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Problem 2990. Replace every 3rd element in a vector with 4

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Last 200 Solutions

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Problem 2990. Replace every 3rd element in a vector with 4

Solution Stats

Last 200 Solutions

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Solution Comments

Problem Recent Solvers263

Suggested Problems

More from this Author28

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Community Treasure Hunt

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