Problem 55. Counting Sequence

Created by Cody Team

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Last Solution submitted on Jun 01, 2023

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Yuri K on 16 Feb 2012

The problem does not define correct solution if same number is not in consecutive order, like x = [5 5 2 1 1 5 3]; Should it be three 5's, or two 5's then one 5? If it's an encoding problem the correct solution should be the last, right?

Richard Zapor on 19 May 2012

Typical DPCM encoding removes the DC and thus starts at 0, not 1. An 11% enhancement in encoding.

Jean-Marie Sainthillier on 22 Jul 2012

Good problem.

Jean-Marie Sainthillier on 13 Mar 2013

Most of the solutions with UNIQUE don't work when same number is not in consecutive order.

Alfonso Nieto-Castanon on 13 Mar 2013

in the new test case 5, with x=[1 2 2 1], the test suite answer is [2 1 2 2] (two 1's, two 2's). I would expect the correct answer to be [1 1 2 2 1 1] (one 1, two 2's, one 1). I guess I am misinterpreting the question?

Jean-Marie Sainthillier on 14 Mar 2013

No. you are right. The test case 5 is wrong.

Ned Gulley on 14 Mar 2013

My mistake guys. Sorry about that. By the way, these comments are very helpful for adding (and fixing) bad test cases. Thanks for taking the time to comment.

Santosh Kumar Choudhary on 28 Sep 2017

Test case 5 answer is wrong. the correct answer is [2 1 2 2]. Change the test case 5 answer

Deepthi Palagati on 19 Sep 2018

test case 5 answer is wrong

Hans Kramer on 23 Oct 2018

Just to clarify: test case 5 isnt wrong.

Sanzhar Askaruly on 7 Jul 2019

wow, last test case is so fun!

Bryan Lambo on 6 Jan 2020

This only took me a few minutes until I saw Case 5 haha! Fun and mind boggling

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Problem 55. Counting Sequence

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