YES We show the termination of the TRS R: le(|0|(),y) -> true() le(s(x),|0|()) -> false() le(s(x),s(y)) -> le(x,y) minus(|0|(),y) -> |0|() minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) if_minus(true(),s(x),y) -> |0|() if_minus(false(),s(x),y) -> s(minus(x,y)) quot(|0|(),s(y)) -> |0|() quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) log(s(|0|())) -> |0|() log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: le#(s(x),s(y)) -> le#(x,y) p2: minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) p3: minus#(s(x),y) -> le#(s(x),y) p4: if_minus#(false(),s(x),y) -> minus#(x,y) p5: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) p6: quot#(s(x),s(y)) -> minus#(x,y) p7: log#(s(s(x))) -> log#(s(quot(x,s(s(|0|()))))) p8: log#(s(s(x))) -> quot#(x,s(s(|0|()))) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The estimated dependency graph contains the following SCCs: {p7} {p5} {p2, p4} {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: log#(s(s(x))) -> log#(s(quot(x,s(s(|0|()))))) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 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!): max/plus interpretation on natural numbers: log#_A(x1) = max{0, x1 - 34} s_A(x1) = x1 + 33 quot_A(x1,x2) = x1 + 21 |0|_A = 8 le_A(x1,x2) = x2 + 39 true_A = 36 false_A = 1 minus_A(x1,x2) = x1 if_minus_A(x1,x2,x3) = max{11, x2} log#!_A(x1) = max{3, x1 - 10} s!_A(x1) = max{23, x1 + 10} quot!_A(x1,x2) = x1 + 22 |0|!_A = 2 le!_A(x1,x2) = max{5, x2 - 1} true!_A = 1 false!_A = 6 minus!_A(x1,x2) = max{4, x1 - 9} if_minus!_A(x1,x2,x3) = max{3, x2 - 23} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: log#_A(x1) = 0 s_A(x1) = 28 quot_A(x1,x2) = max{24, x1 + 21, x2 - 23} |0|_A = 6 le_A(x1,x2) = 22 true_A = 22 false_A = 21 minus_A(x1,x2) = max{1, x1} if_minus_A(x1,x2,x3) = max{28, x1 + 6, x2 - 19} log#!_A(x1) = max{0, x1 - 44} s!_A(x1) = max{0, x1 - 2} quot!_A(x1,x2) = max{6, x1 - 19, x2 - 45} |0|!_A = 27 le!_A(x1,x2) = 0 true!_A = 1 false!_A = 28 minus!_A(x1,x2) = x2 + 26 if_minus!_A(x1,x2,x3) = max{9, x1 - 10, x2 - 20} partial status: pi(log#) = [1] pi(s) = [] pi(quot) = [1] pi(|0|) = [] pi(le) = [] pi(true) = [] pi(false) = [] pi(minus) = [] pi(if_minus) = [2] 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: quot#(s(x),s(y)) -> quot#(minus(x,y),s(y)) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8 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!): max/plus interpretation on natural numbers: quot#_A(x1,x2) = max{0, x1 - 35, x2 - 29} s_A(x1) = max{28, x1 + 18} minus_A(x1,x2) = max{15, x1 + 5} le_A(x1,x2) = 11 |0|_A = 15 true_A = 1 false_A = 11 if_minus_A(x1,x2,x3) = max{27, x1 + 13, x2 + 5} quot_A(x1,x2) = max{39, x1 - 34, x2 - 4} quot#!_A(x1,x2) = max{1, x1 - 16} s!_A(x1) = max{11, x1 - 23} minus!_A(x1,x2) = max{62, x1 + 42} le!_A(x1,x2) = 61 |0|!_A = 10 true!_A = 11 false!_A = 61 if_minus!_A(x1,x2,x3) = max{61, x2 - 36} quot!_A(x1,x2) = max{28, x1 + 25, x2 + 11} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: quot#_A(x1,x2) = max{0, x1 - 22, x2 - 121} s_A(x1) = x1 + 21 minus_A(x1,x2) = x1 le_A(x1,x2) = max{2, x1 - 10} |0|_A = 11 true_A = 2 false_A = 6 if_minus_A(x1,x2,x3) = max{10, x1 + 2, x2} quot_A(x1,x2) = max{22, x1 - 22, x2 - 100} quot#!_A(x1,x2) = x1 + 77 s!_A(x1) = 4 minus!_A(x1,x2) = max{x1 + 99, x2 + 2} le!_A(x1,x2) = 119 |0|!_A = 3 true!_A = 119 false!_A = 119 if_minus!_A(x1,x2,x3) = x1 + 1 quot!_A(x1,x2) = max{6, x1 - 22, x2 - 89} partial status: pi(quot#) = [] pi(s) = [] pi(minus) = [1] pi(le) = [] pi(|0|) = [] pi(true) = [] pi(false) = [] pi(if_minus) = [] pi(quot) = [2] 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: if_minus#(false(),s(x),y) -> minus#(x,y) p2: minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The set of usable rules consists of r1, r2, r3 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!): max/plus interpretation on natural numbers: if_minus#_A(x1,x2,x3) = max{0, x1 - 1, x2 - 37, x3 - 4} false_A = 0 s_A(x1) = max{34, x1 + 25} minus#_A(x1,x2) = max{0, x1 - 37, x2 - 4} le_A(x1,x2) = max{0, x1 - 36, x2 - 21} |0|_A = 20 true_A = 0 if_minus#!_A(x1,x2,x3) = max{2, x1 - 45, x2 - 27, x3 - 1} false!_A = 1 s!_A(x1) = max{3, x1 - 46} minus#!_A(x1,x2) = max{7, x1 - 26, x2 - 1} le!_A(x1,x2) = max{6, x1 - 110, x2 - 44} |0|!_A = 2 true!_A = 3 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: if_minus#_A(x1,x2,x3) = max{0, x1 - 1, x2 - 45, x3 - 16} false_A = 0 s_A(x1) = max{42, x1 + 36} minus#_A(x1,x2) = max{0, x1 - 45, x2 - 16} le_A(x1,x2) = max{0, x1 - 44, x2 - 15} |0|_A = 14 true_A = 0 if_minus#!_A(x1,x2,x3) = max{9, x1 - 42, x2 - 84, x3 - 43} false!_A = 4 s!_A(x1) = max{8, x1 - 51} minus#!_A(x1,x2) = max{9, x1 - 83, x2 - 43} le!_A(x1,x2) = max{10, x1 - 88, x2 - 44} |0|!_A = 3 true!_A = 2 partial status: pi(if_minus#) = [2] pi(false) = [] pi(s) = [1] pi(minus#) = [1] pi(le) = [1] pi(|0|) = [] pi(true) = [] The following rules are removed: p1 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: minus#(s(x),y) -> if_minus#(le(s(x),y),s(x),y) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) The estimated dependency graph contains the following SCCs: (no SCCs) -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: le#(s(x),s(y)) -> le#(x,y) and R consists of: r1: le(|0|(),y) -> true() r2: le(s(x),|0|()) -> false() r3: le(s(x),s(y)) -> le(x,y) r4: minus(|0|(),y) -> |0|() r5: minus(s(x),y) -> if_minus(le(s(x),y),s(x),y) r6: if_minus(true(),s(x),y) -> |0|() r7: if_minus(false(),s(x),y) -> s(minus(x,y)) r8: quot(|0|(),s(y)) -> |0|() r9: quot(s(x),s(y)) -> s(quot(minus(x,y),s(y))) r10: log(s(|0|())) -> |0|() r11: log(s(s(x))) -> s(log(s(quot(x,s(s(|0|())))))) 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!): max/plus interpretation on natural numbers: le#_A(x1,x2) = 0 s_A(x1) = max{3, x1 - 5} le#!_A(x1,x2) = max{0, x2 - 75} s!_A(x1) = max{5, x1 - 74} 2. marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: le#_A(x1,x2) = 0 s_A(x1) = max{9, x1 - 11} le#!_A(x1,x2) = max{6, x1 - 168, x2 - 10} s!_A(x1) = max{5, x1 - 168} partial status: pi(le#) = [2] pi(s) = [1] The following rules are removed: p1 Then no dependency pair remains.