module Test(g) where

data B = TT | FF

g FF FF FF FF y0 y1 y2 y3 = TT
g TT x1 x2 x3 TT y1 y2 y3 = TT
g x0 TT x2 x3 y0 TT y2 y3 = TT
g x0 x1 TT x3 y0 y1 TT y3 = TT
g x0 x1 x2 TT y0 y1 y2 TT = TT
g TT x1 x2 x3 FF y1 y2 y3 = TT
g x0 TT x2 x3 y0 FF y2 y3 = TT
g x0 x1 TT x3 y0 y1 FF y3 = TT
g x0 x1 x2 TT y0 y1 y2 FF = TT