There is double quote interpolation in the first print of the original post. I think this is what the author of the exercise expected. The only problem is that it would not edit the first line. That could be fixed with: 
$" = '#';
print "#@lines";

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The OP's I/O problems hide the fact that he had basically solved the exercise.
Bill

In reply to Re^2: Using $" by BillKSmith
in thread Using $" by Bugz

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