in reply to How can one join the shortest and longest strings of different text files?

I looks like you're about 90% of the way to your solution: you've found the longest and shortest string in each file. Now, what I would do (this is guaranteed to be a less-than-optimal solution) is to a) open the files, using the open function (don't forget to close the files when you're through with them), e.g.,

open(FILE, "<", $this_file) or die "Could not open $this_file because +$!\n";
and, b) scan through the file to find the shortest and longest lines. Store these into hashes:
$long{$file} = $longest_string_in_this_file; $short{$file} = $shortest_string_in_the_same_file;

Repeat for each file, and do whatever joining you wish. If you want to join the two longest and the two shortest lines across files, use a hash of hashes instead of a hash for the longest and shortest lines.

This does seem like an odd question, however. It's not homework, is it?

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