YES We show the termination of the relative TRS R/S: R: app(nil(),k) -> k app(l,nil()) -> l app(cons(x,l),k) -> cons(x,app(l,k)) sum(cons(x,nil())) -> cons(x,nil()) sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) plus(|0|(),y) -> y plus(s(x),y) -> s(plus(x,y)) S: cons(x,cons(y,l)) -> cons(y,cons(x,l)) -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: app#(cons(x,l),k) -> app#(l,k) p2: sum#(cons(x,cons(y,l))) -> sum#(cons(plus(x,y),l)) p3: sum#(cons(x,cons(y,l))) -> plus#(x,y) p4: sum#(app(l,cons(x,cons(y,k)))) -> sum#(app(l,sum(cons(x,cons(y,k))))) p5: sum#(app(l,cons(x,cons(y,k)))) -> app#(l,sum(cons(x,cons(y,k)))) p6: sum#(app(l,cons(x,cons(y,k)))) -> sum#(cons(x,cons(y,k))) p7: plus#(s(x),y) -> plus#(x,y) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The estimated dependency graph contains the following SCCs: {p2, p4, p6} {p1} {p7} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: sum#(app(l,cons(x,cons(y,k)))) -> sum#(cons(x,cons(y,k))) p2: sum#(app(l,cons(x,cons(y,k)))) -> sum#(app(l,sum(cons(x,cons(y,k))))) p3: sum#(cons(x,cons(y,l))) -> sum#(cons(plus(x,y),l)) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: standard order interpretations: sum#_A(x1) = ((0,1),(0,1)) x1 + (10,7) app_A(x1,x2) = ((1,1),(1,1)) x1 + x2 + (9,6) cons_A(x1,x2) = ((1,1),(1,1)) x1 + x2 + (5,5) sum_A(x1) = ((0,1),(0,1)) x1 + (2,0) plus_A(x1,x2) = x2 + (2,2) nil_A() = (1,1) |0|_A() = (1,1) s_A(x1) = (1,1) precedence: sum# = sum > plus > app = cons = nil = |0| = s partial status: pi(sum#) = [] pi(app) = [2] pi(cons) = [] pi(sum) = [] pi(plus) = [] pi(nil) = [] pi(|0|) = [] pi(s) = [] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: sum#(app(l,cons(x,cons(y,k)))) -> sum#(app(l,sum(cons(x,cons(y,k))))) p2: sum#(cons(x,cons(y,l))) -> sum#(cons(plus(x,y),l)) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: sum#(app(l,cons(x,cons(y,k)))) -> sum#(app(l,sum(cons(x,cons(y,k))))) p2: sum#(cons(x,cons(y,l))) -> sum#(cons(plus(x,y),l)) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: standard order interpretations: sum#_A(x1) = x1 + (1,0) app_A(x1,x2) = x1 + ((1,1),(0,1)) x2 + (5,4) cons_A(x1,x2) = ((0,1),(0,1)) x2 + (1,3) sum_A(x1) = (2,6) plus_A(x1,x2) = x2 + (6,7) nil_A() = (1,0) |0|_A() = (1,1) s_A(x1) = (1,1) precedence: app > sum > sum# = cons = plus = s > nil = |0| partial status: pi(sum#) = [1] pi(app) = [] pi(cons) = [] pi(sum) = [] pi(plus) = [2] pi(nil) = [] pi(|0|) = [] pi(s) = [] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: sum#(cons(x,cons(y,l))) -> sum#(cons(plus(x,y),l)) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: sum#(cons(x,cons(y,l))) -> sum#(cons(plus(x,y),l)) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: standard order interpretations: sum#_A(x1) = ((0,1),(0,0)) x1 + (1,0) cons_A(x1,x2) = ((1,0),(1,0)) x2 + (3,1) plus_A(x1,x2) = ((0,1),(1,0)) x1 + ((1,0),(1,1)) x2 + (0,5) app_A(x1,x2) = ((1,0),(1,1)) x1 + ((1,0),(1,1)) x2 + (0,2) nil_A() = (0,0) sum_A(x1) = ((0,0),(1,0)) x1 + (6,7) |0|_A() = (1,1) s_A(x1) = (1,2) precedence: app = |0| > cons = plus = sum > sum# = nil = s partial status: pi(sum#) = [] pi(cons) = [] pi(plus) = [] pi(app) = [] pi(nil) = [] pi(sum) = [] pi(|0|) = [] pi(s) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: app#(cons(x,l),k) -> app#(l,k) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: standard order interpretations: app#_A(x1,x2) = ((1,0),(0,0)) x1 + (5,2) cons_A(x1,x2) = ((1,0),(1,0)) x2 + (4,1) app_A(x1,x2) = x1 + ((1,1),(1,1)) x2 + (5,5) nil_A() = (1,1) sum_A(x1) = ((1,0),(0,0)) x1 + (2,2) plus_A(x1,x2) = x2 + (11,6) |0|_A() = (1,1) s_A(x1) = (1,1) precedence: app = nil = plus > cons = sum > |0| > s > app# partial status: pi(app#) = [] pi(cons) = [] pi(app) = [] pi(nil) = [] pi(sum) = [] pi(plus) = [] pi(|0|) = [] pi(s) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: plus#(s(x),y) -> plus#(x,y) and R consists of: r1: app(nil(),k) -> k r2: app(l,nil()) -> l r3: app(cons(x,l),k) -> cons(x,app(l,k)) r4: sum(cons(x,nil())) -> cons(x,nil()) r5: sum(cons(x,cons(y,l))) -> sum(cons(plus(x,y),l)) r6: sum(app(l,cons(x,cons(y,k)))) -> sum(app(l,sum(cons(x,cons(y,k))))) r7: plus(|0|(),y) -> y r8: plus(s(x),y) -> s(plus(x,y)) r9: cons(x,cons(y,l)) -> cons(y,cons(x,l)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: standard order interpretations: plus#_A(x1,x2) = ((1,0),(1,0)) x1 + (1,2) s_A(x1) = ((1,0),(0,0)) x1 + (2,1) app_A(x1,x2) = x1 + x2 + (2,2) nil_A() = (5,5) cons_A(x1,x2) = (1,1) sum_A(x1) = (4,4) plus_A(x1,x2) = ((1,0),(1,0)) x1 + ((1,1),(1,1)) x2 + (5,5) |0|_A() = (1,1) precedence: plus# = s = nil = plus > app = sum = |0| > cons partial status: pi(plus#) = [] pi(s) = [] pi(app) = [2] pi(nil) = [] pi(cons) = [] pi(sum) = [] pi(plus) = [] pi(|0|) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.