my @RowZero = ("a","b","c");
my @RowOne = ("d","e");
my @RowTwo = ("f","g","h","i");
my @TwoDimArray = (\@RowZero,\@RowOne,\@RowTwo);
my $ChosenRow = 1;

my @chosen_array = @{$TwoDimArray[$ChosenRow]};
my $num_chosen_items = @chosen_array;

print "I chose row $ChosenRow (counting from 0),\n".
      " containing $num_chosen_items things: @chosen_array\n";