# file pal.pl

my $d = shift;
my ($p, $n, @r);

my $r1 = - (9 x $d);
my $r2 = - ((9 x ($d-1)) +1);

IT: for my $f ($r1 .. $r2 ) { 
    for ($f .. $r2) {
        $p = $f * $_;
        last if $p < $r[2];
        if ($p eq reverse $p) {
            if ($n < $p) {
                $n = $p;
                @r = ($f,$_,$p);
                next IT;
            }
        }
    }
    last if -$f**2 < $r[2];
}
print -$r[0]," * ",-$r[1]," = $r[2]\n";
__END__
993 * 913 = 906609

[download]
qwurx [shmem] ~> time perl pal.pl 3
993 * 913 = 906609

real    0m0.004s
user    0m0.000s
sys    0m0.000s

[download]
perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'

In reply to Re: Largest palindrome number for a 3 digit product of 2 numbers by shmem
in thread Largest palindrome number for a 3 digit product of 2 numbers by pr33

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