YES We show the termination of the TRS R: first(|0|(),X) -> nil() first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) from(X) -> cons(X,n__from(n__s(X))) first(X1,X2) -> n__first(X1,X2) from(X) -> n__from(X) s(X) -> n__s(X) activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) activate(n__from(X)) -> from(activate(X)) activate(n__s(X)) -> s(activate(X)) activate(X) -> X -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: first#(s(X),cons(Y,Z)) -> activate#(Z) p2: activate#(n__first(X1,X2)) -> first#(activate(X1),activate(X2)) p3: activate#(n__first(X1,X2)) -> activate#(X1) p4: activate#(n__first(X1,X2)) -> activate#(X2) p5: activate#(n__from(X)) -> from#(activate(X)) p6: activate#(n__from(X)) -> activate#(X) p7: activate#(n__s(X)) -> s#(activate(X)) p8: activate#(n__s(X)) -> activate#(X) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p6, p8} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: first#(s(X),cons(Y,Z)) -> activate#(Z) p2: activate#(n__s(X)) -> activate#(X) p3: activate#(n__from(X)) -> activate#(X) p4: activate#(n__first(X1,X2)) -> activate#(X2) p5: activate#(n__first(X1,X2)) -> activate#(X1) p6: activate#(n__first(X1,X2)) -> first#(activate(X1),activate(X2)) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^1 order: lexicographic order interpretations: first#_A(x1,x2) = x2 + 1 s_A(x1) = x1 cons_A(x1,x2) = x2 activate#_A(x1) = x1 n__s_A(x1) = x1 n__from_A(x1) = x1 + 1 n__first_A(x1,x2) = x1 + x2 + 2 activate_A(x1) = x1 first_A(x1,x2) = x1 + x2 + 2 |0|_A() = 2 nil_A() = 1 from_A(x1) = x1 + 1 precedence: |0| > n__from = from > n__first = first > s = cons = activate# = activate = nil > first# = n__s partial status: pi(first#) = [2] pi(s) = [] pi(cons) = [] pi(activate#) = [] pi(n__s) = [] pi(n__from) = [] pi(n__first) = [] pi(activate) = [1] pi(first) = [] pi(|0|) = [] pi(nil) = [] pi(from) = [] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__s(X)) -> activate#(X) p2: activate#(n__from(X)) -> activate#(X) p3: activate#(n__first(X1,X2)) -> activate#(X2) p4: activate#(n__first(X1,X2)) -> activate#(X1) p5: activate#(n__first(X1,X2)) -> first#(activate(X1),activate(X2)) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__s(X)) -> activate#(X) p2: activate#(n__first(X1,X2)) -> activate#(X1) p3: activate#(n__first(X1,X2)) -> activate#(X2) p4: activate#(n__from(X)) -> activate#(X) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The set of usable rules consists of (no rules) Take the monotone reduction pair: weighted path order base order: matrix interpretations: carrier: N^1 order: lexicographic order interpretations: activate#_A(x1) = x1 n__s_A(x1) = x1 + 1 n__first_A(x1,x2) = x1 + x2 + 1 n__from_A(x1) = x1 + 1 precedence: activate# = n__s = n__first = n__from partial status: pi(activate#) = [1] pi(n__s) = [1] pi(n__first) = [1, 2] pi(n__from) = [1] The next rules are strictly ordered: p4 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__s(X)) -> activate#(X) p2: activate#(n__first(X1,X2)) -> activate#(X1) p3: activate#(n__first(X1,X2)) -> activate#(X2) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The estimated dependency graph contains the following SCCs: {p1, p2, p3} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__s(X)) -> activate#(X) p2: activate#(n__first(X1,X2)) -> activate#(X2) p3: activate#(n__first(X1,X2)) -> activate#(X1) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The set of usable rules consists of (no rules) Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^1 order: lexicographic order interpretations: activate#_A(x1) = x1 n__s_A(x1) = x1 + 1 n__first_A(x1,x2) = x1 + x2 + 1 precedence: activate# = n__s = n__first partial status: pi(activate#) = [] pi(n__s) = [1] pi(n__first) = [2] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__first(X1,X2)) -> activate#(X2) p2: activate#(n__first(X1,X2)) -> activate#(X1) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__first(X1,X2)) -> activate#(X2) p2: activate#(n__first(X1,X2)) -> activate#(X1) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The set of usable rules consists of (no rules) Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^1 order: lexicographic order interpretations: activate#_A(x1) = x1 + 1 n__first_A(x1,x2) = x1 + x2 + 2 precedence: activate# = n__first partial status: pi(activate#) = [] pi(n__first) = [2] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__first(X1,X2)) -> activate#(X1) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: activate#(n__first(X1,X2)) -> activate#(X1) and R consists of: r1: first(|0|(),X) -> nil() r2: first(s(X),cons(Y,Z)) -> cons(Y,n__first(X,activate(Z))) r3: from(X) -> cons(X,n__from(n__s(X))) r4: first(X1,X2) -> n__first(X1,X2) r5: from(X) -> n__from(X) r6: s(X) -> n__s(X) r7: activate(n__first(X1,X2)) -> first(activate(X1),activate(X2)) r8: activate(n__from(X)) -> from(activate(X)) r9: activate(n__s(X)) -> s(activate(X)) r10: activate(X) -> X The set of usable rules consists of (no rules) Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^1 order: lexicographic order interpretations: activate#_A(x1) = x1 n__first_A(x1,x2) = x1 + x2 + 1 precedence: activate# = n__first partial status: pi(activate#) = [] pi(n__first) = [2] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.