%Hidlabels = (3333=>1, 4444=>2, 2222=>3);
$formula =~ s{ (\d+) }
             { defined $Hidlabels{$1} ? $Hidlabels{$1} : $1 }xeg
             if $formula =~ /^f/;

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In reply to Re: help required for regexp by tobyink
in thread help required for regexp by upaksh

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