my $file;
open $file, '<', $temperature_path or die $!;
$temperature = <$file>;
-close $file;
+close $file or die $!;
open $file, '<', $critical_path or die $!;
$critical = <$file>;
-close $file;
+close $file or die $!;
my $value = int($temperature / 1000);
my $risk = ($critical - $temperature)/$critical;