YES (VAR x y z u v) (RULES and(null(nil()),null(nil())) -> null(nil()) null(end(x,y)) -> false() true() -> null(nil()) .(end(x,y),z) -> .(x,f(y,z)) .(nil(),y) -> y f(x,end(y,z)) -> end(f(x,y),z) f(x,nil()) -> end(nil(),x) eq(end(x,y),end(u,v)) -> and(eq(y,v),eq(x,u)) eq(end(x,y),nil()) -> false() eq(nil(),end(y,z)) -> false() eq(x,x) -> null(nil()) ) (COMMENT Termination is shown by KBO with weight w0 = 2 w(eq) = 4 w(true) = 6 w(nil) = 2 w(end) = 3 w(false) = 2 w(and) = 0 w(f) = 3 w(.) = 0 w(null) = 2 and precedence: and > eq > null > true > nil > false > f > . > end )