That's the first solution that comes to my mind. Try reading it backwards:

1. Take the keys of the hash... (keys %hash)
2. ...sort them numerically... (sort { $a <=> $b } ...)
3. ...and get the first element of the array corresponding to each key in the hash... (map { $hash{$_}->[0] } ...)

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In reply to Re: Problem with HOA. by cog
in thread Problem with HOA. by tamaguchi

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