type Data = (Int, Int, String)

bottom (b, _, _) = b
top    (_, t, _) = t
ide    (_, _, i) = i

contains :: Data -> Data -> Bool
x `contains` y = bottom x <= bottom y && top x >= top y

rangeSort1 :: [Data] -> [(Data, [Data])]
rangeSort1 r = map (\x -> (x, (filter (contains x) (filter (/=x) r))))  r

----

test :: [Data]
test = [ (11, 22, "A")
       , (22, 45, "B")
       , (22, 33, "C")
       , (25, 28, "D")
       , (47, 49, "E")
       ]

##</code><code>##

sub bottom { shift->[0] };
sub top    { shift->[1] };
sub ide    { shift->[2] };

sub contains { bottom($_[0]) <= bottom($_[1]) && top($_[0]) >= top($_[1]) };

sub rangeSort1 { map { my $x = $_;
                       [$x, [grep {contains($x, $_)}
                                 (grep { ide($_) ne ide($x) } @_) ] ]
                   } @_ };

my $test = [ [11, 22, "A"]
           , [22, 45, "B"]
           , [22, 33, "C"]
           , [25, 28, "D"]
           , [47, 49, "E"]
       ];

##</code><code>##

rangeSort1 :: [Data] -> [(Data, [Data])]
rangeSort1 r = mapMaybe (\x -> let l = filter (contains x) . filter (/=x)
                               in case l r of
                                 []        -> Nothing
                                 otherwise -> Just (x, l r)
                        )  r