#!/usr/bin/perl -wp
1 while s/-(\d+),(??{1+$1})-/-/
	or s/-(\d+),((??{1+$1}))\b/-$2/
	or s/\b(\d+),(??{1+$1})-/$1-/
	or s/\b(\d+),((??{1+$1}))\b/$1-$2/;