open(E,shift @ARGV) or die($!); chomp(@e=<E>); close(E);
undef $/; $t=<>;
printf("%-20s : %3d\n", "Words:" ,scalar split(' ',$t));
printf("%-20s : %3d\n ", $_, scalar(@a=($t =~ m/$_/mgi)))
for @e;
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Good enough to do the work, bad enough to fail a test. As a homework assignment, find out how this works and then rewrite it in a decent way.

Hint: takes as arguments one file with a list of words/expressions and a list of files to be processed.