* Title:adder and subtracter- tutorial
* Designer:lopsidation
* Type:Puzzle (1)
* Follows:
* Physics:1
             ,  , |  O + O  O:         :L        f
               )  |  O   O  O:         :L51      T
       O <<<<<M=  |  OM.WO  O:         :L         
      O  ,  ,+M   |  OM1WO  O:  07     :L        L
 O   O    (       |  OMOWO  O:  4b     :L92      b
  O O     +M===   |         O:         :L        T
   O      h       |         O: DDD     :L         
|       >:xM      |         O: D0D     :L78       
|            11)  |         O: +TD     :L        T
|=================|     2 OOO:   D     :L        6
                  |     TOO:O:>:::::::::LLLLLLLLLL
                  |     1O.~wwwwwwwwwwwZZZZZZZZZZZ
       O   O   O  |NNNNNNNNNw         wZ          
      O     O O   |        Nw     d   wZ          
 O   O       O    |   +    Nw d       wZ          
  O O       O O   |   3    Nw   4     wZ          
   O       O   O  |  .==   Nw      2  wZ     :    
      + | +       |22      Nw         wZ31        
(11     |      11)|TTN     NwT        wZTT        
========|=========|44      Nw5        wZ21        
DDDDDDDDDDDDDZZZZZZZZZZZZHHHHHHHHHHHHQQQQQQQQQQQQQ
            DZ          ZH5         HQ            
   - - - -  DZ          ZH7         HQ            
  hg g g g  DZ     -    ZH7         HQ     + + +  
  ========= DZ          ZH4         HQ (1  2 2 2  
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   + + + +  DZ $..>=WZZ ZH4       + HQQQQQQQQQQQQQ
  hg g g g  DZ$1$$$$$ Z ZHc2f7d7e4 0HQ            
  ========= DZ >>>>>>TZ ZH>>>>>>>>T<HQ +   -  +   
            DZ      Z0Z ZHHHHHHHHHbHHQ11  21 37