Term Rewriting System R: [x, a, k, y] f(x, empty) -> x f(empty, cons(a, k)) -> f(cons(a, k), k) f(cons(a, k), y) -> f(y, k) Termination of R to be shown. Removing the following rules from R which fullfill a polynomial ordering: f(x, empty) -> x where the Polynomial interpretation: POL(f(x_1, x_2)) = 1 + x_1 + 2*x_2 POL(empty) = 0 POL(cons(x_1, x_2)) = x_1 + 2*x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: f(empty, cons(a, k)) -> f(cons(a, k), k) where the Polynomial interpretation: POL(f(x_1, x_2)) = 2 + x_1 + 2*x_2 POL(empty) = 1 POL(cons(x_1, x_2)) = x_1 + 2*x_2 was used. Not all Rules of R can be deleted, so we still have to regard a part of R. Removing the following rules from R which fullfill a polynomial ordering: f(cons(a, k), y) -> f(y, k) where the Polynomial interpretation: POL(f(x_1, x_2)) = 2 + x_1 + x_2 POL(cons(x_1, x_2)) = 1 + x_1 + x_2 was used. All Rules of R can be deleted. Termination of R successfully shown. Duration: 0.388 seconds.