YES We show the termination of the relative TRS R/S: R: minus(x,|0|()) -> x minus(s(x),s(y)) -> minus(x,y) quot(|0|(),s(y)) -> |0|() quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) app(nil(),y) -> y app(add(n,x),y) -> add(n,app(x,y)) reverse(nil()) -> nil() reverse(add(n,x)) -> app(reverse(x),add(n,nil())) shuffle(nil()) -> nil() shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) concat(leaf(),y) -> y concat(cons(u,v),y) -> cons(u,concat(v,y)) less_leaves(x,leaf()) -> false() less_leaves(leaf(),cons(w,z)) -> true() less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) S: rand(x) -> x rand(x) -> rand(s(x)) -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: minus#(s(x),s(y)) -> minus#(x,y) p2: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) p3: quot#(s(x),s(y)) -> minus#(x,y) p4: app#(add(n,x),y) -> app#(x,y) p5: reverse#(add(n,x)) -> app#(reverse(x),add(n,nil())) p6: reverse#(add(n,x)) -> reverse#(x) p7: shuffle#(add(n,x)) -> shuffle#(reverse(x)) p8: shuffle#(add(n,x)) -> reverse#(x) p9: concat#(cons(u,v),y) -> concat#(v,y) p10: less_leaves#(cons(u,v),cons(w,z)) -> less_leaves#(concat(u,v),concat(w,z)) p11: less_leaves#(cons(u,v),cons(w,z)) -> concat#(u,v) p12: less_leaves#(cons(u,v),cons(w,z)) -> concat#(w,z) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The estimated dependency graph contains the following SCCs: {p2} {p1} {p7} {p6} {p4} {p10} {p9} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^3 order: lexicographic order interpretations: quot#_A(x1,x2) = ((1,0,0),(0,1,0),(0,1,1)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 s_A(x1) = x1 + (0,2,1) minus_A(x1,x2) = x1 + (0,0,1) |0|_A() = (1,1,1) quot_A(x1,x2) = ((1,0,0),(0,1,0),(1,1,1)) x1 + ((0,0,0),(1,0,0),(0,1,0)) x2 + (1,1,0) app_A(x1,x2) = ((1,0,0),(1,0,0),(1,0,0)) x1 + ((1,0,0),(0,1,0),(0,1,0)) x2 + (0,1,0) nil_A() = (0,2,2) add_A(x1,x2) = ((1,0,0),(1,0,0),(0,1,0)) x1 + ((1,0,0),(0,1,0),(1,0,0)) x2 + (4,2,0) reverse_A(x1) = ((1,0,0),(1,1,0),(1,1,0)) x1 shuffle_A(x1) = ((1,0,0),(1,0,0),(0,1,0)) x1 + (1,1,0) concat_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,1,0),(0,0,1)) x2 + (6,4,1) leaf_A() = (1,1,1) cons_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((0,0,0),(1,0,0),(0,1,0)) x2 + (1,1,1) less_leaves_A(x1,x2) = (1,0,0) false_A() = (0,1,1) true_A() = (0,1,1) rand_A(x1) = x1 + (1,1,1) 2. lexicographic path order with precedence: precedence: leaf > true > quot# > rand > quot > less_leaves > reverse > cons > app > false > nil > s > concat > shuffle > add > |0| > minus argument filter: pi(quot#) = 1 pi(s) = [] pi(minus) = [] pi(|0|) = [] pi(quot) = 1 pi(app) = [] pi(nil) = [] pi(add) = [] pi(reverse) = [] pi(shuffle) = [] pi(concat) = 2 pi(leaf) = [] pi(cons) = 1 pi(less_leaves) = [] pi(false) = [] pi(true) = [] pi(rand) = [] 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: minus#(s(x),s(y)) -> minus#(x,y) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^3 order: lexicographic order interpretations: minus#_A(x1,x2) = ((1,0,0),(0,1,0),(0,1,1)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 s_A(x1) = x1 + (0,1,1) minus_A(x1,x2) = x1 |0|_A() = (1,1,1) quot_A(x1,x2) = ((1,0,0),(0,1,0),(0,1,0)) x1 + x2 + (1,0,0) app_A(x1,x2) = ((0,0,0),(0,0,0),(1,0,0)) x1 + x2 + (4,2,0) nil_A() = (1,0,1) add_A(x1,x2) = ((0,0,0),(0,0,0),(1,0,0)) x1 + (3,1,4) reverse_A(x1) = ((1,0,0),(1,1,0),(0,0,1)) x1 + (5,0,6) shuffle_A(x1) = x1 + (0,0,1) concat_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,1,0),(1,1,1)) x2 + (1,4,1) leaf_A() = (1,1,1) cons_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,0,0),(1,1,0)) x2 + (2,1,1) less_leaves_A(x1,x2) = ((1,0,0),(0,1,0),(1,1,1)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 false_A() = (0,2,3) true_A() = (0,3,0) rand_A(x1) = x1 + (1,1,1) 2. lexicographic path order with precedence: precedence: concat > quot > cons > add > nil > shuffle > minus# > s > true > |0| > rand > leaf > minus > reverse > less_leaves > app > false argument filter: pi(minus#) = 2 pi(s) = 1 pi(minus) = 1 pi(|0|) = [] pi(quot) = [2] pi(app) = [] pi(nil) = [] pi(add) = [] pi(reverse) = 1 pi(shuffle) = 1 pi(concat) = 1 pi(leaf) = [] pi(cons) = 1 pi(less_leaves) = 1 pi(false) = [] pi(true) = [] pi(rand) = [] 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: shuffle#(add(n,x)) -> shuffle#(reverse(x)) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^3 order: lexicographic order interpretations: shuffle#_A(x1) = ((0,0,0),(1,0,0),(0,1,0)) x1 add_A(x1,x2) = ((1,0,0),(0,1,0),(0,1,0)) x2 + (0,1,1) reverse_A(x1) = x1 + (0,0,3) minus_A(x1,x2) = x1 + (1,1,1) |0|_A() = (1,3,1) s_A(x1) = x1 + (0,1,1) quot_A(x1,x2) = ((0,0,0),(0,0,0),(1,0,0)) x1 + ((0,0,0),(1,0,0),(1,1,0)) x2 + (2,2,1) app_A(x1,x2) = ((1,0,0),(0,1,0),(0,1,0)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 + (0,0,1) nil_A() = (0,0,1) shuffle_A(x1) = x1 + (1,1,1) concat_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,1,0),(1,0,1)) x2 + (1,4,1) leaf_A() = (1,1,1) cons_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,0,0),(1,1,0)) x2 + (2,1,1) less_leaves_A(x1,x2) = ((1,0,0),(0,1,0),(1,1,1)) x1 + ((1,0,0),(0,0,0),(0,1,0)) x2 false_A() = (0,1,0) true_A() = (0,0,0) rand_A(x1) = x1 + (1,1,1) 2. lexicographic path order with precedence: precedence: quot > s > leaf > shuffle > less_leaves > false > minus > concat > rand > reverse > app > add > nil > |0| > shuffle# > true > cons argument filter: pi(shuffle#) = [] pi(add) = [] pi(reverse) = [1] pi(minus) = [] pi(|0|) = [] pi(s) = [] pi(quot) = [] pi(app) = [2] pi(nil) = [] pi(shuffle) = [] pi(concat) = [1, 2] pi(leaf) = [] pi(cons) = 1 pi(less_leaves) = [1] pi(false) = [] pi(true) = [] pi(rand) = [] 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: reverse#(add(n,x)) -> reverse#(x) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^3 order: lexicographic order interpretations: reverse#_A(x1) = ((0,0,0),(1,0,0),(0,0,0)) x1 add_A(x1,x2) = x1 + x2 + (4,0,1) minus_A(x1,x2) = ((1,0,0),(0,1,0),(1,0,1)) x1 + ((0,0,0),(0,0,0),(1,0,0)) x2 |0|_A() = (1,1,1) s_A(x1) = x1 + (0,1,1) quot_A(x1,x2) = x1 + (1,1,0) app_A(x1,x2) = ((1,0,0),(0,0,0),(1,0,0)) x1 + x2 nil_A() = (0,1,2) reverse_A(x1) = ((1,0,0),(0,0,0),(1,0,0)) x1 + (0,2,2) shuffle_A(x1) = ((1,0,0),(1,1,0),(1,1,0)) x1 + (0,1,0) concat_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,1,0),(1,1,1)) x2 + (1,5,1) leaf_A() = (1,1,1) cons_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,0,0),(1,1,0)) x2 + (3,1,5) less_leaves_A(x1,x2) = ((1,0,0),(0,1,0),(1,1,1)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 false_A() = (0,0,0) true_A() = (0,0,10) rand_A(x1) = x1 + (1,1,1) 2. lexicographic path order with precedence: precedence: cons > reverse# > rand > leaf > shuffle > less_leaves > quot > concat > |0| > true > reverse > app > add > false > nil > s > minus argument filter: pi(reverse#) = [] pi(add) = [] pi(minus) = [] pi(|0|) = [] pi(s) = [] pi(quot) = [1] pi(app) = [2] pi(nil) = [] pi(reverse) = [] pi(shuffle) = [] pi(concat) = [] pi(leaf) = [] pi(cons) = [1] pi(less_leaves) = [1, 2] pi(false) = [] pi(true) = [] pi(rand) = [] 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#(add(n,x),y) -> app#(x,y) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^3 order: lexicographic order interpretations: app#_A(x1,x2) = ((1,0,0),(1,1,0),(1,0,1)) x1 + ((0,0,0),(1,0,0),(0,1,0)) x2 add_A(x1,x2) = x2 + (2,1,1) minus_A(x1,x2) = ((1,0,0),(0,1,0),(0,1,1)) x1 + (0,0,1) |0|_A() = (1,1,1) s_A(x1) = x1 + (0,1,1) quot_A(x1,x2) = ((1,0,0),(0,1,0),(0,1,0)) x1 + (1,1,1) app_A(x1,x2) = ((1,0,0),(1,0,0),(1,0,0)) x1 + x2 nil_A() = (0,1,2) reverse_A(x1) = ((1,0,0),(1,0,0),(1,0,0)) x1 + (0,2,1) shuffle_A(x1) = ((1,0,0),(0,1,0),(0,1,1)) x1 + (1,0,0) concat_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,1,0),(1,1,1)) x2 + (1,3,1) leaf_A() = (1,1,1) cons_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,0,0),(1,1,0)) x2 + (3,1,1) less_leaves_A(x1,x2) = ((1,0,0),(0,1,0),(1,1,1)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 false_A() = (0,0,0) true_A() = (0,0,0) rand_A(x1) = x1 + (1,1,1) 2. lexicographic path order with precedence: precedence: rand > false > cons > leaf > true > less_leaves > reverse > quot > s > concat > |0| > shuffle > minus > app > add > nil > app# argument filter: pi(app#) = [] pi(add) = [] pi(minus) = [] pi(|0|) = [] pi(s) = [] pi(quot) = [] pi(app) = [2] pi(nil) = [] pi(reverse) = [] pi(shuffle) = [1] pi(concat) = [] pi(leaf) = [] pi(cons) = [1] pi(less_leaves) = [1, 2] pi(false) = [] pi(true) = [] pi(rand) = [] 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: less_leaves#(cons(u,v),cons(w,z)) -> less_leaves#(concat(u,v),concat(w,z)) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^3 order: lexicographic order interpretations: less_leaves#_A(x1,x2) = ((1,0,0),(1,1,0),(1,0,0)) x1 + ((1,0,0),(1,0,0),(0,1,0)) x2 cons_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(0,1,0),(1,1,1)) x2 + (3,1,6) concat_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,1,0),(0,1,1)) x2 + (1,6,1) minus_A(x1,x2) = x1 + ((0,0,0),(0,0,0),(1,0,0)) x2 + (1,1,1) |0|_A() = (1,1,1) s_A(x1) = x1 + (0,0,1) quot_A(x1,x2) = ((0,0,0),(0,0,0),(1,0,0)) x1 + ((1,0,0),(1,1,0),(0,1,1)) x2 + (2,2,1) app_A(x1,x2) = x2 nil_A() = (0,0,1) add_A(x1,x2) = x2 reverse_A(x1) = ((0,0,0),(1,0,0),(0,0,0)) x1 + (0,0,2) shuffle_A(x1) = ((1,0,0),(1,1,0),(1,1,0)) x1 + (1,1,2) leaf_A() = (1,1,1) less_leaves_A(x1,x2) = ((1,0,0),(0,1,0),(1,1,1)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 false_A() = (0,0,0) true_A() = (0,0,0) rand_A(x1) = x1 + (1,1,1) 2. lexicographic path order with precedence: precedence: rand > quot > cons > s > minus > less_leaves > leaf > false > shuffle > reverse > true > app > less_leaves# > add > nil > |0| > concat argument filter: pi(less_leaves#) = [] pi(cons) = 1 pi(concat) = 1 pi(minus) = [] pi(|0|) = [] pi(s) = [] pi(quot) = [2] pi(app) = 2 pi(nil) = [] pi(add) = 2 pi(reverse) = [] pi(shuffle) = [] pi(leaf) = [] pi(less_leaves) = [1, 2] pi(false) = [] pi(true) = [] pi(rand) = [] 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: concat#(cons(u,v),y) -> concat#(v,y) and R consists of: r1: minus(x,|0|()) -> x r2: minus(s(x),s(y)) -> minus(x,y) r3: quot(|0|(),s(y)) -> |0|() r4: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r5: app(nil(),y) -> y r6: app(add(n,x),y) -> add(n,app(x,y)) r7: reverse(nil()) -> nil() r8: reverse(add(n,x)) -> app(reverse(x),add(n,nil())) r9: shuffle(nil()) -> nil() r10: shuffle(add(n,x)) -> add(n,shuffle(reverse(x))) r11: concat(leaf(),y) -> y r12: concat(cons(u,v),y) -> cons(u,concat(v,y)) r13: less_leaves(x,leaf()) -> false() r14: less_leaves(leaf(),cons(w,z)) -> true() r15: less_leaves(cons(u,v),cons(w,z)) -> less_leaves(concat(u,v),concat(w,z)) r16: rand(x) -> x r17: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14, r15, r16, r17 Take the reduction pair: lexicographic combination of reduction pairs: 1. matrix interpretations: carrier: N^3 order: lexicographic order interpretations: concat#_A(x1,x2) = x1 + ((0,0,0),(1,0,0),(0,1,0)) x2 cons_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,0,0),(1,1,0)) x2 + (2,1,1) minus_A(x1,x2) = x1 + x2 + (1,1,1) |0|_A() = (1,1,1) s_A(x1) = x1 + (0,1,1) quot_A(x1,x2) = ((0,0,0),(0,0,0),(1,0,0)) x1 + ((0,0,0),(1,0,0),(0,0,0)) x2 + (2,2,2) app_A(x1,x2) = ((1,0,0),(0,0,0),(1,0,0)) x1 + x2 + (0,1,1) nil_A() = (0,1,1) add_A(x1,x2) = ((1,0,0),(0,0,0),(1,0,0)) x1 + x2 + (4,0,1) reverse_A(x1) = ((1,0,0),(0,0,0),(1,0,0)) x1 + (0,3,2) shuffle_A(x1) = ((1,0,0),(1,1,0),(1,1,1)) x1 + (0,1,0) concat_A(x1,x2) = ((1,0,0),(1,1,0),(1,1,1)) x1 + ((1,0,0),(1,1,0),(1,1,1)) x2 + (1,4,1) leaf_A() = (1,1,1) less_leaves_A(x1,x2) = ((1,0,0),(0,1,0),(1,1,1)) x1 + ((1,0,0),(0,1,0),(0,1,1)) x2 false_A() = (0,2,3) true_A() = (0,0,0) rand_A(x1) = x1 + (1,1,1) 2. lexicographic path order with precedence: precedence: leaf > concat > concat# > true > |0| > false > reverse > app > less_leaves > nil > add > quot > s > cons > rand > shuffle > minus argument filter: pi(concat#) = [] pi(cons) = [] pi(minus) = [] pi(|0|) = [] pi(s) = [] pi(quot) = [] pi(app) = [2] pi(nil) = [] pi(add) = [] pi(reverse) = [] pi(shuffle) = 1 pi(concat) = [] pi(leaf) = [] pi(less_leaves) = [] pi(false) = [] pi(true) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.