That means that the first open() call failed. Either use autodie; in the beginning, or write your calls as 
open my $IN, '<', 'transaction' or die "Cannot open 'transaction' for 
+reading: $!";
...
while (<$IN>) {
   ...
}

[download]

(And adapt the code for the second file accordingly).

Perl 6 - second systems done right

In reply to Re^3: split line from one point by moritz
in thread split line from one point by Anonymous Monk

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