Input TRS: 1: fib(N) -> sel(N,fib1(s(0()),s(0()))) 2: fib1(X,Y) -> cons(X,fib1(Y,add(X,Y))) 3: add(0(),X) -> X 4: add(s(X),Y) -> s(add(X,Y)) 5: sel(0(),cons(X,XS)) -> X 6: sel(s(N),cons(X,XS)) -> sel(N,XS) Number of strict rules: 6 Direct Order(PosReal,>,Poly) ... failed. Freezing ... failed. Dependency Pairs: #1: #fib1(X,Y) -> #fib1(Y,add(X,Y)) #2: #fib1(X,Y) -> #add(X,Y) #3: #sel(s(N),cons(X,XS)) -> #sel(N,XS) #4: #fib(N) -> #sel(N,fib1(s(0()),s(0()))) #5: #fib(N) -> #fib1(s(0()),s(0())) #6: #add(s(X),Y) -> #add(X,Y) Number of SCCs: 3, DPs: 3, edges: 3 SCC { #6 } Removing DPs: Order(PosReal,>,Sum)... succeeded. s(x1) weight: (/ 1 2) + x1 #fib1(x1,x2) weight: 0 fib1(x1,x2) weight: 0 fib(x1) weight: 0 0() weight: 0 #sel(x1,x2) weight: 0 sel(x1,x2) weight: 0 cons(x1,x2) weight: 0 #add(x1,x2) weight: x1 add(x1,x2) weight: 0 #fib(x1) weight: 0 Usable rules: { } Removed DPs: #6 Number of SCCs: 2, DPs: 2, edges: 2 SCC { #1 } Removing DPs: Order(PosReal,>,Sum)... Order(PosReal,>,Max)... QLPOpS... Order(PosReal,>,MaxSum)... QWPOpS(PosReal,>,MaxSum)... Order(PosReal,>,Sum-Sum; PosReal,≥,Sum-Sum)... Order(PosReal,>,Sum-Sum; NegReal,≥,Sum)... Order(PosReal,>,MaxSum-Sum; NegReal,≥,Sum)... failed. Removing edges: failed. Finding a loop... found. #fib1(X,X_{1}) -#1-> #fib1(X_{1},add(X,X_{1})) --->* #fib1(X_{1},add(X,X_{1})) Looping with: [ X := X_{1}; X_{1} := add(X,X_{1}); ] NO