open FILE, $file or die $!;
my @array = <FILE>;
close FILE;
my $i = @array; 
while( $i-- ){
    my $j=int rand(1+$i);
    next if $i == $j;
    @array[$i, $j]=@array[$j, $i]
}

open OUT, ">$out" or die $!;
print OUT @array;
close OUT: