$hash{$array[0]} = { $array[1] => $array[2] };

##</code><code>##

$hash{$array[0]}{$array[1]} = $array[2];

##</code><code>##

$hash{$array[0]} = {} if not defined $hash{$array[0]};
$hash{$array[0]}{$array[1]} = $array[2];