m"K"=[1,2] m"Q"=m"B"++m"R" m"R"=[1,4,9] m"B"=[2,8,18] m"N"=[5] m"P"=[2] f[_]=[[]]
[((0, 0), "B"), ((2, 0), "B"), ((0, 2), "P"), ((2, 2), "K"), ((3, 1), "N"), ((3, 3), "R")]
[((0,0),(2,2)),((3,3),(3,1)),((2,2),(3,1)),((3,1),(2,0)),((2,0),(0,2))] [((0,0),(3,3)),((3,3),(2,2)),((2,2),(3,1)),((3,1),(2,0)),((2,0),(0,2))] [((3,3),(3,1)),((0,0),(2,2)),((2,2),(3,1)),((3,1),(2,0)),((2,0),(0,2))]