Some collegues are first to the punch

mildside has 

m/^\d((?<=\d)\d(?=([ \d]|$))|(?<=[\d ]) (?=( |$))){19}$/

[download]
another is 
m/^(?=\d*(?:\d ) *(?!\d)$)[0-9 ]{20}$/

[download]

+++++++++++++++++
#!/usr/bin/perl
use warnings;use strict;use brain;

In reply to Re: Regex to match 20 chars of some digits followed by some spaces by leriksen
in thread Regex to match 20 chars of some digits followed by some spaces by leriksen

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