#!/usr/bin/perl

use strict;
use List::Util qw(shuffle);
use Data::Dumper;

#undef $/;
#$/='';

my %ac=();
my @l=1..20;

print join(",",shuffle(@l));

for (1..1000){
  my ($a,$b)= _choice( @{[20..(int(rand(10))>8 ? 40 : 30)]} ) ;
  $ac{$b}++;
  print "Res: $a / $b\n"
}

print Dumper(\%ac);
 

sub _choice{ my @a=@_; my $i = int(rand(scalar @a)); ($a[$i], $i)}