OK, here's an example. It's not anything like a useful random number generator for cryptographic purposes, but looks fairly random at a first glance...

use v5.12;

{
    my $seed = time;
    sub myrand
    {
        do {
            $seed *= $seed;
            $seed =~ s/[^0-9]//g;
            my $midpoint = int(length($seed) / 2);
            $seed = substr($seed, 0, $midpoint) . substr($seed, $midpo
+int);
            $seed = substr($seed, 0, 9);
        } until ($seed > 10_000_000);
        my $r   = reverse substr($seed, 0, 6);
        my $lim = @_ ? shift : 1;
        $lim * ($r/1_000_000);
    }
}

# 50 random numbers less than 10...
say myrand(10) for 1..50;

[download]
package Cow { use Moo; has name => (is => 'lazy', default => sub { 'Mooington' }) } say Cow->new->name

In reply to Re: generate random number without using any built in function in perl? by tobyink
in thread generate random number without using any built in function in perl? by anurag_perl

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