WORST_CASE(?,O(n^1)) Solution: --------- "0" :: [] -(0)-> "Nat"(15) "checkF" :: ["Q"(2)] -(11)-> "Q"(2) "cons" :: ["Nat"(0) x "L"(2)] -(2)-> "L"(2) "cons" :: ["Nat"(0) x "L"(0)] -(0)-> "L"(0) "empty" :: [] -(3)-> "Q"(2) "enq" :: ["Nat"(15)] -(4)-> "Q"(2) "errorHead" :: [] -(0)-> "Nat"(7) "errorTail" :: [] -(0)-> "Q"(7) "head" :: ["Q"(8)] -(8)-> "Nat"(0) "nil" :: [] -(0)-> "L"(2) "nil" :: [] -(0)-> "L"(0) "nil" :: [] -(0)-> "L"(7) "nil" :: [] -(0)-> "L"(15) "queue" :: ["L"(0) x "L"(2)] -(2)-> "Q"(2) "queue" :: ["L"(0) x "L"(8)] -(8)-> "Q"(8) "queue" :: ["L"(0) x "L"(4)] -(4)-> "Q"(4) "rev" :: ["L"(2)] -(9)-> "L"(0) "rev'" :: ["L"(2) x "L"(0)] -(8)-> "L"(0) "s" :: ["Nat"(15)] -(15)-> "Nat"(15) "snoc" :: ["Q"(2) x "Nat"(0)] -(14)-> "Q"(2) "tail" :: ["Q"(8)] -(15)-> "Q"(0) Cost Free Signatures: --------------------- Base Constructors: ------------------ "\"0\"_Nat" :: [] -(0)-> "Nat"(1) "\"cons\"_L" :: ["Nat"(0) x "L"(1)] -(1)-> "L"(1) "\"errorHead\"_Nat" :: [] -(0)-> "Nat"(1) "\"errorTail\"_Q" :: [] -(0)-> "Q"(1) "\"nil\"_L" :: [] -(0)-> "L"(1) "\"queue\"_Q" :: ["L"(0) x "L"(1)] -(1)-> "Q"(1) "\"s\"_Nat" :: ["Nat"(1)] -(1)-> "Nat"(1)