#!/usr/bin/perl

use strict;

my $numrgx = qr/^-?[\d.]+(?:e[+-]\d{2})?$/;

my @try_these = ( 
    "0.2000000000000001",
    "0.3000000000000001"
);

for ( @try_these ) {
    my $x = my $y = $_;
    $y .= "1";

    my $same = ( $x eq $y );
    if ( ! $same and
         ( $x =~ /^-?\.?\d/ and $x =~ /$numrgx/ ) and
         ( $y =~ /^-?\.?\d/ and $y =~ /$numrgx/ )) {
        $same = ( $x == $y );
    }
    my $cmp = ( $same ) ? "is the same as" : "differs from";

    print "$x $cmp $y\n";
}


##</code><code>##

0.2000000000000001 differs from 0.20000000000000011
0.3000000000000001 is the same as 0.30000000000000011

##</code><code>##

#!/usr/bin/perl

use strict;

my $numrgx = qr/^-?(?:\d+\.?\d*|\d*\.\d+)(?:e[+-]?\d{1,2})?$/;

my @try_these = ( @ARGV == 2 ) ? ( $ARGV[0] ) :
( 
    "0.2000000000000001",
    "0.3000000000000001"
);

for ( @try_these ) {
    my $x = $_;
    my $y = ( @ARGV == 2 ) ? $ARGV[1] : $_ . "1";
    my $same = ( $x eq $y );
    if ( ! $same and
         ( $x =~ /$numrgx/ ) and
         ( $y =~ /$numrgx/ )) {
        $same = ( $x == $y );
    }
    my $cmp = ( $same ) ? "is the same as" : "differs from";

    print "$x $cmp $y\n";
}