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

Solution Stats

392 Solutions
132 Solvers

Last Solution submitted on May 04, 2020

Last 200 Solutions

Problem Comments

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

Problem Recent Solvers132

Problem Tags

arrays math sequences

Problem 594. "Look and say" sequence

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers132

Suggested Problems

More from this Author3

Problem Tags

Problem 594. "Look and say" sequence

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers132

Suggested Problems

More from this Author3

Problem Tags

Players