use strict;
use warnings;

use v5.12;

use constant TOP   =>  1000000;

say "1 is prime.";
say "2 is prime.";

my $found = 2; # We already found 1 and 2.
for( my $i = 3; $i < TOP; $i += 2 ) {
    my $qualifies = 1;
    for( my $j = $i - 2; $j > 1; $j -= 2 ) {
        if( $i % $j == 0 ){
            $qualifies = 0;
            last;
        }
    }
    if( $qualifies ) {
        say "$i is prime.";
        $found++;
    }
}
say "Found $found primes between 1 and ", TOP, ".\n";