# [[0 for j in range(4)] for i in range(3)]
R = {'a', 'b'}
C = {'#','@','?'}

{ ((j+1)*10**i for j in range(4) for i in range(3) }

M = Mat(({'a', 'b'}, {'#','@','?'}), {('a', '#'):1, ('a', '@'):2, ('a', '?'):3, ('b', '#'):10, ('b', '@'):20, ('b', '?'):30})

