I am a newbie, so please be kind. I want to have a comma seperated number(every three digits). The following I have works for the first three digits, but if the number is 7 digits longs it doesnt add the comma. I know I'm missing something really simple. 
$col=~s/(\d)(\d\d\d)$/$1,$2/g;

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In reply to simple regex by Anonymous Monk

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