It's not at all clear from your question if you need a "data structure" at all. You could simply read line by line, pattern-match the "HOUR" lines, and indent the U, L, and D lines to the hour column, perhaps using something like: 
my $spaces = $hour * 8;
my $padding = ' ' x $spaces;

[download]
It also appears you want to skip U/L/D blocks when there is no HOUR header. Is that correct?

In reply to Re: Formatting questions by tall_man
in thread Formatting questions by Anonymous Monk

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