use Readonly;
Readonly $C1 => 1;

my $t0 = time();
my $a = 2;
for (1 .. 10000000) {
	if ($a ++ == $C1) {
		;
	}
}
print time() - $t0;

##</code><code>##

use constant C1 => 1;

my $t0 = time();
my $a = 2;
for (1 .. 10000000) {
	if ($a ++ == C1) {
		;
	}
}
print time() - $t0;