Three-Room Monte

This is one of the new possible maps for Sokoban Level 4 in Hack'EM. It has 12 boulders and 10 holes, leaving 2 spare boulders.

--------   ---- 0 boulder
|......-----??| ^ hole
|..>...^^^^^..| > starting position/downstairs
|.0..0.------^| < upstairs
|..0.0.|....|^| ? scroll of earth
|--0.---.0..|^|
|..0.0.0..0.|^|
|......|0.0.|^|
----...|....|<|
   ------------

Strategy

--------   ---- A urrr rr
|......-----??| B lllu rrrr r
|..>...^^^^^..| F ruuu urrr rr
|.A..B.------^| G luuu urrr rrr
|..C.D.|....|^|
|--E.---.J..|^|
|..F.G.H..K.|^|
|......|I.L.|^|
----...|....|<|
   ------------

--------   ---- C r
|......-----??| E duuu urrr rrrr r
|..>.......^..| C uurr rrrr rrrd
|......------^| D luur rrrr rrrr dd
|..C.D.|....|^|
|--E.---.J..|^|
|......H..K.|^|
|......|I.L.|^|
----...|....|<|
   ------------

--------   ---- H rr
|......-----??| J r
|..>..........| H d
|......------.| K llll lluu uurr rrrr rrrd dd
|......|....|.| L ulll lllu uuur rrrr rrrr dddd
|--..---.J..|^| J dlll lllu uuur rrrr rrrr dddd d
|......H..K.|^|
|......|I.L.|^|
----...|....|<|
   ------------