YES We show the termination of the TRS R: if(true(),x,y) -> x if(false(),x,y) -> y eq(|0|(),|0|()) -> true() eq(|0|(),s(x)) -> false() eq(s(x),|0|()) -> false() eq(s(x),s(y)) -> eq(x,y) app(nil(),l) -> l app(cons(x,l1),l2) -> cons(x,app(l1,l2)) app(app(l1,l2),l3) -> app(l1,app(l2,l3)) mem(x,nil()) -> false() mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) ifmem(true(),x,l) -> true() ifmem(false(),x,l) -> mem(x,l) inter(x,nil()) -> nil() inter(nil(),x) -> nil() inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) ifinter(false(),x,l1,l2) -> inter(l1,l2) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: eq#(s(x),s(y)) -> eq#(x,y) p2: app#(cons(x,l1),l2) -> app#(l1,l2) p3: app#(app(l1,l2),l3) -> app#(l1,app(l2,l3)) p4: app#(app(l1,l2),l3) -> app#(l2,l3) p5: mem#(x,cons(y,l)) -> ifmem#(eq(x,y),x,l) p6: mem#(x,cons(y,l)) -> eq#(x,y) p7: ifmem#(false(),x,l) -> mem#(x,l) p8: inter#(app(l1,l2),l3) -> app#(inter(l1,l3),inter(l2,l3)) p9: inter#(app(l1,l2),l3) -> inter#(l1,l3) p10: inter#(app(l1,l2),l3) -> inter#(l2,l3) p11: inter#(l1,app(l2,l3)) -> app#(inter(l1,l2),inter(l1,l3)) p12: inter#(l1,app(l2,l3)) -> inter#(l1,l2) p13: inter#(l1,app(l2,l3)) -> inter#(l1,l3) p14: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p15: inter#(cons(x,l1),l2) -> mem#(x,l2) p16: inter#(l1,cons(x,l2)) -> ifinter#(mem(x,l1),x,l2,l1) p17: inter#(l1,cons(x,l2)) -> mem#(x,l1) p18: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p19: ifinter#(false(),x,l1,l2) -> inter#(l1,l2) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: {p9, p10, p12, p13, p14, p16, p18, p19} {p5, p7} {p1} {p2, p3, p4} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: ifinter#(false(),x,l1,l2) -> inter#(l1,l2) p2: inter#(l1,cons(x,l2)) -> ifinter#(mem(x,l1),x,l2,l1) p3: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p4: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p5: inter#(l1,app(l2,l3)) -> inter#(l1,l3) p6: inter#(l1,app(l2,l3)) -> inter#(l1,l2) p7: inter#(app(l1,l2),l3) -> inter#(l2,l3) p8: inter#(app(l1,l2),l3) -> inter#(l1,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r3, r4, r5, r6, r10, r11, r12, r13 Take the reduction pair: max/plus interpretations on natural numbers: ifinter#_A(x1,x2,x3,x4) = max{x1 + 2, x3 + 4, x4 + 3} false_A = 0 inter#_A(x1,x2) = max{x1 + 4, x2 + 3} cons_A(x1,x2) = max{x1, x2 + 2} mem_A(x1,x2) = 0 true_A = 0 app_A(x1,x2) = max{x1, x2} eq_A(x1,x2) = 2 |0|_A = 0 s_A(x1) = max{0, x1 - 1} ifmem_A(x1,x2,x3) = 0 nil_A = 0 The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: ifinter#(false(),x,l1,l2) -> inter#(l1,l2) p2: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p3: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p4: inter#(l1,app(l2,l3)) -> inter#(l1,l3) p5: inter#(l1,app(l2,l3)) -> inter#(l1,l2) p6: inter#(app(l1,l2),l3) -> inter#(l2,l3) p7: inter#(app(l1,l2),l3) -> inter#(l1,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p5, p6, p7} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: ifinter#(false(),x,l1,l2) -> inter#(l1,l2) p2: inter#(app(l1,l2),l3) -> inter#(l1,l3) p3: inter#(app(l1,l2),l3) -> inter#(l2,l3) p4: inter#(l1,app(l2,l3)) -> inter#(l1,l2) p5: inter#(l1,app(l2,l3)) -> inter#(l1,l3) p6: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p7: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r3, r4, r5, r6, r10, r11, r12, r13 Take the reduction pair: max/plus interpretations on natural numbers: ifinter#_A(x1,x2,x3,x4) = max{x1 + 2, x4 + 5} false_A = 3 inter#_A(x1,x2) = x2 + 5 app_A(x1,x2) = max{x1 + 1, x2} cons_A(x1,x2) = max{0, x1 - 5, x2 - 3} mem_A(x1,x2) = 3 true_A = 0 eq_A(x1,x2) = max{5, x1, x2 - 2} |0|_A = 5 s_A(x1) = x1 + 5 ifmem_A(x1,x2,x3) = 3 nil_A = 0 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: ifinter#(false(),x,l1,l2) -> inter#(l1,l2) p2: inter#(app(l1,l2),l3) -> inter#(l1,l3) p3: inter#(app(l1,l2),l3) -> inter#(l2,l3) p4: inter#(l1,app(l2,l3)) -> inter#(l1,l3) p5: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p6: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p5, p6} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: ifinter#(false(),x,l1,l2) -> inter#(l1,l2) p2: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p3: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p4: inter#(l1,app(l2,l3)) -> inter#(l1,l3) p5: inter#(app(l1,l2),l3) -> inter#(l2,l3) p6: inter#(app(l1,l2),l3) -> inter#(l1,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r3, r4, r5, r6, r10, r11, r12, r13 Take the reduction pair: max/plus interpretations on natural numbers: ifinter#_A(x1,x2,x3,x4) = max{x1 + 6, x2 + 6, x3 + 6} false_A = 1 inter#_A(x1,x2) = max{6, x1 + 5} cons_A(x1,x2) = max{x1 + 2, x2 + 2} mem_A(x1,x2) = 1 true_A = 0 app_A(x1,x2) = max{1, x1, x2} eq_A(x1,x2) = 3 |0|_A = 0 s_A(x1) = max{0, x1 - 1} ifmem_A(x1,x2,x3) = 1 nil_A = 0 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: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p2: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p3: inter#(l1,app(l2,l3)) -> inter#(l1,l3) p4: inter#(app(l1,l2),l3) -> inter#(l2,l3) p5: inter#(app(l1,l2),l3) -> inter#(l1,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p5} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p2: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p3: inter#(app(l1,l2),l3) -> inter#(l1,l3) p4: inter#(app(l1,l2),l3) -> inter#(l2,l3) p5: inter#(l1,app(l2,l3)) -> inter#(l1,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r3, r4, r5, r6, r10, r11, r12, r13 Take the reduction pair: max/plus interpretations on natural numbers: inter#_A(x1,x2) = x2 + 1 cons_A(x1,x2) = max{0, x1 - 4, x2 - 3} ifinter#_A(x1,x2,x3,x4) = max{x1 + 1, x4 + 1} mem_A(x1,x2) = 0 true_A = 0 app_A(x1,x2) = max{x1 - 1, x2 + 1} eq_A(x1,x2) = 3 |0|_A = 0 s_A(x1) = max{0, x1 - 1} false_A = 0 ifmem_A(x1,x2,x3) = 0 nil_A = 0 The next rules are strictly ordered: p5 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p2: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p3: inter#(app(l1,l2),l3) -> inter#(l1,l3) p4: inter#(app(l1,l2),l3) -> inter#(l2,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) 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: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p2: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p3: inter#(app(l1,l2),l3) -> inter#(l2,l3) p4: inter#(app(l1,l2),l3) -> inter#(l1,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r3, r4, r5, r6, r10, r11, r12, r13 Take the reduction pair: max/plus interpretations on natural numbers: inter#_A(x1,x2) = x1 + 2 cons_A(x1,x2) = max{x1, x2} ifinter#_A(x1,x2,x3,x4) = max{x1 + 2, x2 + 1, x3 + 2} mem_A(x1,x2) = 0 true_A = 0 app_A(x1,x2) = max{x1 + 1, x2} eq_A(x1,x2) = 2 |0|_A = 0 s_A(x1) = max{0, x1 - 1} false_A = 0 ifmem_A(x1,x2,x3) = 0 nil_A = 2 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: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p2: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p3: inter#(app(l1,l2),l3) -> inter#(l2,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) 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: inter#(cons(x,l1),l2) -> ifinter#(mem(x,l2),x,l1,l2) p2: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p3: inter#(app(l1,l2),l3) -> inter#(l2,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r3, r4, r5, r6, r10, r11, r12, r13 Take the reduction pair: max/plus interpretations on natural numbers: inter#_A(x1,x2) = x1 + 6 cons_A(x1,x2) = max{x1 - 2, x2 + 1} ifinter#_A(x1,x2,x3,x4) = max{x2 + 1, x3 + 6} mem_A(x1,x2) = max{x1 + 3, x2 + 3} true_A = 3 app_A(x1,x2) = max{x1 - 5, x2} eq_A(x1,x2) = max{x1 + 4, x2} |0|_A = 3 s_A(x1) = x1 + 3 false_A = 3 ifmem_A(x1,x2,x3) = max{x1 - 1, x2 + 3, x3 + 3} nil_A = 0 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: ifinter#(true(),x,l1,l2) -> inter#(l1,l2) p2: inter#(app(l1,l2),l3) -> inter#(l2,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: {p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: inter#(app(l1,l2),l3) -> inter#(l2,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of (no rules) Take the reduction pair: max/plus interpretations on natural numbers: inter#_A(x1,x2) = x1 app_A(x1,x2) = max{x1 + 1, x2 + 1} The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: ifmem#(false(),x,l) -> mem#(x,l) p2: mem#(x,cons(y,l)) -> ifmem#(eq(x,y),x,l) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r3, r4, r5, r6 Take the reduction pair: max/plus interpretations on natural numbers: ifmem#_A(x1,x2,x3) = max{x1 - 2, x3 + 1} false_A = 0 mem#_A(x1,x2) = max{1, x2} cons_A(x1,x2) = max{x1 + 1, x2 + 2} eq_A(x1,x2) = max{0, x2 - 1} |0|_A = 0 true_A = 0 s_A(x1) = x1 The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: ifmem#(false(),x,l) -> mem#(x,l) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: (no SCCs) -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: eq#(s(x),s(y)) -> eq#(x,y) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of (no rules) Take the reduction pair: max/plus interpretations on natural numbers: eq#_A(x1,x2) = max{x1 + 1, x2 + 1} s_A(x1) = x1 + 1 The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: app#(cons(x,l1),l2) -> app#(l1,l2) p2: app#(app(l1,l2),l3) -> app#(l2,l3) p3: app#(app(l1,l2),l3) -> app#(l1,app(l2,l3)) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of r7, r8, r9 Take the reduction pair: max/plus interpretations on natural numbers: app#_A(x1,x2) = x1 + 4 cons_A(x1,x2) = max{2, x1, x2} app_A(x1,x2) = max{x1 + 2, x2} nil_A = 0 The next rules are strictly ordered: p3 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: app#(cons(x,l1),l2) -> app#(l1,l2) p2: app#(app(l1,l2),l3) -> app#(l2,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: app#(cons(x,l1),l2) -> app#(l1,l2) p2: app#(app(l1,l2),l3) -> app#(l2,l3) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of (no rules) Take the reduction pair: max/plus interpretations on natural numbers: app#_A(x1,x2) = max{0, x1 - 1} cons_A(x1,x2) = x2 + 1 app_A(x1,x2) = max{x1 + 2, x2 + 2} The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: app#(cons(x,l1),l2) -> app#(l1,l2) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: app#(cons(x,l1),l2) -> app#(l1,l2) and R consists of: r1: if(true(),x,y) -> x r2: if(false(),x,y) -> y r3: eq(|0|(),|0|()) -> true() r4: eq(|0|(),s(x)) -> false() r5: eq(s(x),|0|()) -> false() r6: eq(s(x),s(y)) -> eq(x,y) r7: app(nil(),l) -> l r8: app(cons(x,l1),l2) -> cons(x,app(l1,l2)) r9: app(app(l1,l2),l3) -> app(l1,app(l2,l3)) r10: mem(x,nil()) -> false() r11: mem(x,cons(y,l)) -> ifmem(eq(x,y),x,l) r12: ifmem(true(),x,l) -> true() r13: ifmem(false(),x,l) -> mem(x,l) r14: inter(x,nil()) -> nil() r15: inter(nil(),x) -> nil() r16: inter(app(l1,l2),l3) -> app(inter(l1,l3),inter(l2,l3)) r17: inter(l1,app(l2,l3)) -> app(inter(l1,l2),inter(l1,l3)) r18: inter(cons(x,l1),l2) -> ifinter(mem(x,l2),x,l1,l2) r19: inter(l1,cons(x,l2)) -> ifinter(mem(x,l1),x,l2,l1) r20: ifinter(true(),x,l1,l2) -> cons(x,inter(l1,l2)) r21: ifinter(false(),x,l1,l2) -> inter(l1,l2) The set of usable rules consists of (no rules) Take the reduction pair: max/plus interpretations on natural numbers: app#_A(x1,x2) = x1 cons_A(x1,x2) = max{x1 + 1, x2 + 1} The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.