#! perl -slw
use strict;
use Statistics::ChiSquare qw[ chisquare chisquaredVal ];
use Math::Random::MT;
use Data::Dump qw[ pp ];

my $mt = Math::Random::MT->new();

our $N          //= 1e6;
our $ASIZE      //= 4;
our $T          //= 4;

sub     shuffle {
        $a = $_ + $mt->rand( @_ - $_ ),
        $b = $_[$_],
        $_[$_] = $_[$a],
        $_[$a] = $b
                for 0 .. $#_;
        return @_;
}

my @data = ( 1 .. $ASIZE );
my @chi;
for( 1 .. $T ) {
    my %tests;
    ++$tests{ join '', shuffle( @data ) } for 1 .. $N;
    push @chi, chisquaredVal( values %tests );
}