If you just want to insert a space between a digit and a minus sign: 
while (<>) {
    s/(\d)-/$1 -/g;
    print;
}

[download]

Are you sure the output isn't in a fixed-width format?

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re: match digit, followed by hyphen, followed again by digit - then add whitespaces and replace in file by choroba
in thread match digit, followed by hyphen, followed again by digit - then add whitespaces and replace in file by fasoli

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