i have this two files below. the first one produces no errors but the second one produces the following errors:

Global symbol "$x" requires explicit package name (did you forget to declare "my $x"?) at ./two.pl line 6.
Global symbol "$y" requires explicit package name (did you forget to declare "my $y"?) at ./two.pl line 7.
Global symbol "$x" requires explicit package name (did you forget to declare "my $x"?) at ./two.pl line 10.
Global symbol "$y" requires explicit package name (did you forget to declare "my $y"?) at ./two.pl line 13.
Global symbol "$x" requires explicit package name (did you forget to declare "my $x"?) at ./two.pl line 15.
Global symbol "$y" requires explicit package name (did you forget to declare "my $y"?) at ./two.pl line 15.
Execution of ./two.pl aborted due to compilation errors.

this is file 1:

#!/usr/bin/perl

use warnings;
use strict;

$a=0;

chomp($a=<STDIN>);
print $a, "\n";
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and this is file 2:

#!/usr/bin/perl

use warnings;
use strict;

$x=0;
$y=0;

print "enter first number ";
chomp($x=<STDIN>);

print "enter second number ";
chomp($y=<STDIN>);

print "Product ",$x*$y, "\n";
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i can't seem to figure out what's causing the errors for file 2. the declaration is the same in both files.