WORST_CASE(?,O(n^2)) Solution: --------- "+" :: ["A"(0, 0) x "A"(2, 0)] -(1)-> "A"(0, 0) "0" :: [] -(0)-> "A"(0, 0) "0" :: [] -(0)-> "A"(2, 0) "0" :: [] -(0)-> "A"(4, 0) "s" :: ["A"(0, 0)] -(0)-> "A"(0, 0) "s" :: ["A"(2, 0)] -(2)-> "A"(2, 0) Cost Free Signatures: --------------------- "+" :: ["A"_cf(0, 0) x "A"_cf(0, 0)] -(0)-> "A"_cf(0, 0) "+" :: ["A"_cf(2, 0) x "A"_cf(2, 0)] -(0)-> "A"_cf(2, 0) "0" :: [] -(0)-> "A"_cf(0, 0) "0" :: [] -(0)-> "A"_cf(2, 0) "0" :: [] -(0)-> "A"_cf(2, 1) "s" :: ["A"_cf(0, 0)] -(0)-> "A"_cf(0, 0) "s" :: ["A"_cf(2, 0)] -(2)-> "A"_cf(2, 0) Base Constructors: ------------------