YES We show the termination of the TRS 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))) minus(minus(x,y),z) -> minus(x,plus(y,z)) plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) plus(zero(),y) -> y plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) id(x) -> x if(true(),x,y) -> x if(false(),x,y) -> y not(x) -> if(x,false(),true()) gt(s(x),zero()) -> true() gt(zero(),y) -> false() gt(s(x),s(y)) -> gt(x,y) -- SCC decomposition. Consider the 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: minus#(minus(x,y),z) -> minus#(x,plus(y,z)) p5: minus#(minus(x,y),z) -> plus#(y,z) p6: plus#(s(x),s(y)) -> plus#(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))) p7: plus#(s(x),s(y)) -> if#(gt(x,y),x,y) p8: plus#(s(x),s(y)) -> gt#(x,y) p9: plus#(s(x),s(y)) -> if#(not(gt(x,y)),id(x),id(y)) p10: plus#(s(x),s(y)) -> not#(gt(x,y)) p11: plus#(s(x),s(y)) -> id#(x) p12: plus#(s(x),s(y)) -> id#(y) p13: plus#(s(x),x) -> plus#(if(gt(x,x),id(x),id(x)),s(x)) p14: plus#(s(x),x) -> if#(gt(x,x),id(x),id(x)) p15: plus#(s(x),x) -> gt#(x,x) p16: plus#(s(x),x) -> id#(x) p17: plus#(id(x),s(y)) -> plus#(x,if(gt(s(y),y),y,s(y))) p18: plus#(id(x),s(y)) -> if#(gt(s(y),y),y,s(y)) p19: plus#(id(x),s(y)) -> gt#(s(y),y) p20: not#(x) -> if#(x,false(),true()) p21: gt#(s(x),s(y)) -> gt#(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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The estimated dependency graph contains the following SCCs: {p2} {p1, p4} {p6, p13, p17} {p21} -- Reduction pair. Consider the 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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of r1, r2, r5 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: quot#_A(x1,x2) = 0 s_A(x1) = x1 + 3 minus_A(x1,x2) = x1 + 1 |0|_A() = 0 plus_A(x1,x2) = x1 + 1 quot#!_A(x1,x2) = 3 s!_A(x1) = 5 minus!_A(x1,x2) = 4 |0|!_A() = 0 plus!_A(x1,x2) = 3 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: quot#_A(x1,x2) = max{0, x2 - 98} s_A(x1) = max{33, x1 + 8} minus_A(x1,x2) = max{30, x1 + 4} |0|_A = 49 plus_A(x1,x2) = max{80, x1 - 80} quot#!_A(x1,x2) = max{0, x1 - 6} s!_A(x1) = max{42, x1 - 2} minus!_A(x1,x2) = max{0, x1 - 3} |0|!_A = 41 plus!_A(x1,x2) = max{26, x1 - 80, x2 + 17} partial status: pi(quot#) = [] pi(s) = [1] pi(minus) = [1] pi(|0|) = [] pi(plus) = [] The following rules are removed: p1 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: minus#(s(x),s(y)) -> minus#(x,y) p2: minus#(minus(x,y),z) -> minus#(x,plus(y,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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of (no rules) Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: minus#_A(x1,x2) = 0 s_A(x1) = x1 + 1 minus_A(x1,x2) = x1 + 2 plus_A(x1,x2) = 0 minus#!_A(x1,x2) = x1 + 2 s!_A(x1) = x1 + 3 minus!_A(x1,x2) = 6 plus!_A(x1,x2) = 5 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: minus#_A(x1,x2) = 0 s_A(x1) = 5 minus_A(x1,x2) = 0 plus_A(x1,x2) = 7 minus#!_A(x1,x2) = 0 s!_A(x1) = 0 minus!_A(x1,x2) = max{2, x2 - 11} plus!_A(x1,x2) = max{3, x1 - 67} partial status: pi(minus#) = [] pi(s) = [] pi(minus) = [1, 2] pi(plus) = [1] The following rules are removed: p1, p2 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: plus#(s(x),s(y)) -> plus#(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))) p2: plus#(id(x),s(y)) -> plus#(x,if(gt(s(y),y),y,s(y))) p3: plus#(s(x),x) -> plus#(if(gt(x,x),id(x),id(x)),s(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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of r10, r11, r12, r14, r15, r16 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: plus#_A(x1,x2) = 0 s_A(x1) = x1 + 2 if_A(x1,x2,x3) = x2 + x3 + 1 gt_A(x1,x2) = x1 + 1 not_A(x1) = x1 + 2 id_A(x1) = x1 + 1 true_A() = 1 false_A() = 1 zero_A() = 1 plus#!_A(x1,x2) = 4 s!_A(x1) = x1 + 6 if!_A(x1,x2,x3) = 3 gt!_A(x1,x2) = x2 + 5 not!_A(x1) = 7 id!_A(x1) = 4 true!_A() = 0 false!_A() = 0 zero!_A() = 1 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: plus#_A(x1,x2) = 0 s_A(x1) = max{43, x1 + 38} if_A(x1,x2,x3) = max{x2 + 6, x3} gt_A(x1,x2) = max{77, x1 - 43} not_A(x1) = 77 id_A(x1) = x1 + 31 true_A = 63 false_A = 1 zero_A = 43 plus#!_A(x1,x2) = max{15, x1 - 5, x2 - 43} s!_A(x1) = 72 if!_A(x1,x2,x3) = max{74, x2 - 22, x3 - 63} gt!_A(x1,x2) = max{74, x1 + 37, x2 - 151} not!_A(x1) = x1 + 76 id!_A(x1) = 72 true!_A = 15 false!_A = 75 zero!_A = 76 partial status: pi(plus#) = [] pi(s) = [1] pi(if) = [2, 3] pi(gt) = [2] pi(not) = [1] pi(id) = [1] pi(true) = [] pi(false) = [] pi(zero) = [] The following rules are removed: p3 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: plus#(s(x),s(y)) -> plus#(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))) p2: plus#(id(x),s(y)) -> plus#(x,if(gt(s(y),y),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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: plus#(s(x),s(y)) -> plus#(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))) p2: plus#(id(x),s(y)) -> plus#(x,if(gt(s(y),y),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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of r10, r11, r12, r13, r14, r15, r16 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: plus#_A(x1,x2) = 0 s_A(x1) = 7 if_A(x1,x2,x3) = x2 + x3 gt_A(x1,x2) = 1 not_A(x1) = x1 + 2 id_A(x1) = x1 + 3 true_A() = 1 false_A() = 1 zero_A() = 1 plus#!_A(x1,x2) = 6 s!_A(x1) = 8 if!_A(x1,x2,x3) = 14 gt!_A(x1,x2) = 1 not!_A(x1) = 15 id!_A(x1) = x1 + 7 true!_A() = 0 false!_A() = 0 zero!_A() = 1 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: plus#_A(x1,x2) = max{0, x1 - 66, x2 - 49} s_A(x1) = x1 + 44 if_A(x1,x2,x3) = max{32, x1 - 61, x2, x3} gt_A(x1,x2) = max{79, x2 - 1} not_A(x1) = max{35, x1 - 44} id_A(x1) = max{48, x1 + 27} true_A = 27 false_A = 27 zero_A = 0 plus#!_A(x1,x2) = max{17, x1 - 19, x2 - 25} s!_A(x1) = 5 if!_A(x1,x2,x3) = max{16, x1 - 46, x2 - 28, x3 - 28} gt!_A(x1,x2) = max{3, x1 - 37, x2 - 45} not!_A(x1) = max{26, x1 - 2} id!_A(x1) = max{6, x1 - 20} true!_A = 4 false!_A = 0 zero!_A = 5 partial status: pi(plus#) = [] pi(s) = [1] pi(if) = [1, 2, 3] pi(gt) = [] pi(not) = [1] pi(id) = [1] pi(true) = [] pi(false) = [] pi(zero) = [] The following rules are removed: p1 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: plus#(id(x),s(y)) -> plus#(x,if(gt(s(y),y),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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: plus#(id(x),s(y)) -> plus#(x,if(gt(s(y),y),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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of r11, r12, r14, r15, r16 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: plus#_A(x1,x2) = x1 id_A(x1) = x1 s_A(x1) = x1 + 4 if_A(x1,x2,x3) = x2 + x3 + 5 gt_A(x1,x2) = x1 + 1 true_A() = 1 false_A() = 1 zero_A() = 1 plus#!_A(x1,x2) = 4 id!_A(x1) = 15 s!_A(x1) = x1 + 3 if!_A(x1,x2,x3) = 16 gt!_A(x1,x2) = x2 + 2 true!_A() = 0 false!_A() = 0 zero!_A() = 1 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: plus#_A(x1,x2) = max{0, x2 - 179} id_A(x1) = max{66, x1 - 25} s_A(x1) = x1 + 150 if_A(x1,x2,x3) = max{178, x1 + 130, x2 + 28, x3} gt_A(x1,x2) = max{46, x1 - 227, x2 - 123} true_A = 46 false_A = 46 zero_A = 0 plus#!_A(x1,x2) = max{33, x1 - 31} id!_A(x1) = max{59, x1 + 24} s!_A(x1) = max{3, x1 - 25} if!_A(x1,x2,x3) = max{x1 + 122, x2 - 92, x3 - 92} gt!_A(x1,x2) = max{34, x1 - 151, x2 - 151} true!_A = 0 false!_A = 0 zero!_A = 1 partial status: pi(plus#) = [1] pi(id) = [1] pi(s) = [] pi(if) = [1, 2, 3] pi(gt) = [] pi(true) = [] pi(false) = [] pi(zero) = [] The following rules are removed: p1 Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: gt#(s(x),s(y)) -> gt#(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: minus(minus(x,y),z) -> minus(x,plus(y,z)) r6: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r7: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r8: plus(zero(),y) -> y r9: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r10: id(x) -> x r11: if(true(),x,y) -> x r12: if(false(),x,y) -> y r13: not(x) -> if(x,false(),true()) r14: gt(s(x),zero()) -> true() r15: gt(zero(),y) -> false() r16: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of (no rules) Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: trivial reduction triple (T x T, T x T, Φ) base order 2: lexicographic combination of reduction triples: 1. marked-algebra reduction triple (>=A, >=A!, >A!): matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: gt#_A(x1,x2) = x1 + x2 s_A(x1) = x1 + 4 gt#!_A(x1,x2) = x1 s!_A(x1) = x1 + 9 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: gt#_A(x1,x2) = 0 s_A(x1) = max{13, x1 - 21} gt#!_A(x1,x2) = max{16, x1 - 14, x2 - 14} s!_A(x1) = max{15, x1 + 11} partial status: pi(gt#) = [] pi(s) = [1] The following rules are removed: p1 Then no dependency pair remains.