Problem 594. "Look and say" sequence

Created by Alex Feinman

Solve Later

What's the next number in this sequence?

[0]
[1 0]
[1 1 1 0]
[3 1 1 0]
[1 3 2 1 1 0]

This a variant on the well-known "look and say" or Morris sequence, where each new iteration is made up by 'saying' the number of numbers you see. That last line is "one 3; then two 1s; then one 0".

Create a function that returns the next element of this sequence, given a vector as a starting seed..

Solve

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402 Solutions
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Last Solution submitted on Jun 25, 2020

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3 Comments

3 Comments

Tim on 17 Apr 2012

Test suite case 3 seems to be incorrect.

@bmtran (Bryant Tran) on 17 Apr 2012

yeah, test case 3 should be [1 1 2 3 1 1 1 5 2 2] by my calculation

Alex Feinman on 17 Apr 2012

Sorry about that. Cut and paste fail.

Solution Comments

Solution 1788201

1 Comment

1 Comment

Thara Jose on 15 Apr 2019

I tried solving this in MATLAB & it gave correct answer for the 3rd test suite also

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Problem 594. "Look and say" sequence

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Last 200 Solutions

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Problem 594. "Look and say" sequence

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Last 200 Solutions

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Problem Recent Solvers167

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