Problem 91. Get the area codes from a list of phone numbers

Created by Cody Team

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1608 Solutions
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Last Solution submitted on Jan 15, 2021

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blaat on 10 Feb 2012

An explanation of common notations of area codes would be nice for us non-Americans :)

Aurelien Queffurust on 30 Mar 2012

I (as French) Agree. A Wikipedia link which would explain supported area codes is definitely missing.

David Verrelli on 14 Dec 2017

"You can assume the first three digits of a ten-digit number will always be the area code." Hmmm.... too bad there was no explanation applying to telephone numbers with more (or less?) than ten digits.

Rafael S.T. Vieira on 12 Jun 2020

The problem fails to mention that the area codes should be sorted, and that phone numbers may have country codes.

Rik on 15 Jan 2021 at 8:35

This isn't about American-style phone numbers, but US-style. Otherwise it would be nice to include other test cases so people would be required to actually parse the country code away. Now it is just a matter of removing a leading 1.

Solution Comments

Solution 4602245

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Rik on 15 Jan 2021 at 9:35

I thought I would document my regex, as it looks fairly complex at first glance.

Solution 1195679

1 Comment

1 Comment

Informaton on 23 May 2017

Apparently the order needs to be the same as that defined by the test suite; which is not in the order of the phone numbers given :(

Solution 443029

1 Comment

1 Comment

Pascal Geschwill on 15 May 2014

Is there a way to execute regexp/regexprep with multiple expresssions at the same time?

Solution 398499

1 Comment

1 Comment

Informaton on 23 May 2017

regexp hack

Solution 372579

1 Comment

1 Comment

Robert on 19 Dec 2013

Not sure what's going on here, but it works in my actual MATLAB program, and Octave.

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Problem 91. Get the area codes from a list of phone numbers

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Problem 91. Get the area codes from a list of phone numbers

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