`````S`KSKxx'x''             # B = S(KS)K
`x`x'x''                     # Bxyz = x(yz)
`````S``S`K``S`KSKS`KKxx'x'' # C = S(S(K(S(KS)K))S)(KK) = S(S(KB)S)(KK)
``xx''x'                     # Cxyz = xzy
````SS`K``SKKxx'             # W = SS(K(SKK))
``xx'x'                      # Wxy = xyy