i am new to perl and want some help in tuning this script if possible cause it takes time if i increased my array. also if i "use warnings" i get a lot of warnings which im unable to handle. im using perl (v5.24.0) built for darwin-thread-multi-2level

    my $start_run = time();
    use strict;
    use Benchmark;
    use warnings;
    my @array = (1..1000000000);
    foreach (@array) {
       if ($_==reverse(substr($_, 0, 1) * substr($_, 1)))
          { print $_."\n" ;}
        if ($_==reverse(substr($_, 0, 2) * substr($_, 2)))
        { print $_."\n" ;}
        if ($_==reverse(substr($_, 0, 3) * substr($_, 3)))
        { print $_."\n" ;}
        if ($_==reverse(substr($_, 0, 4) * substr($_, 4)))
        { print $_."\n" ;}
        if ($_==reverse(substr($_, 0, 5) * substr($_, 5)))
        { print $_."\n" ;}
        if ($_==reverse(substr($_, 0, 6) * substr($_, 6)))
        { print $_."\n" ;}
        if ($_==reverse(substr($_, 0, 7) * substr($_, 7)))
        { print $_."\n" ;}
    }
    my $end_run = time();
    my $run_time = $end_run - $start_run;
    print "Time taken: ".$run_time." sec\n";
[download]

thanks to everyone who has helped, i have now been able with the new ideas to write the code this way which has a good performance now </>

use strict;
use warnings;

use Time::HiRes qw( time );

my $start_run = time();

for my $n (100..1_00_000_000) {
    my $r = reverse($n);
    
    my $x = 100;
    while ($x <= $n) {
        if (int($n / $x) * ($n % $x) == $r) {
            print "$n\n";
            last;
        }
        
        $x *= 10;
    }
}

my $end_run = time();
my $run_time = $end_run - $start_run;
print "Time taken: ".$run_time." sec\n";
[download]

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