use strict;
use warnings;
my $filename = "C:/mlb_boxscore107238$4820.txt";
open(INPUT, '<'.$filename) or die "Can't open $filename: $!\n";

##</code><code>##

Name "main::INPUT" used only once: possible typo at test.pl line 4.
Use of uninitialized value in concatenation (.) at test.pl line 3.
Can't open C:/mlb_boxscore107238.txt: No such file or directory