YES We show the termination of the TRS R: times(x,plus(y,|1|())) -> plus(times(x,plus(y,times(|1|(),|0|()))),x) times(x,|1|()) -> x times(x,|0|()) -> |0|() 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: times#(x,plus(y,|1|())) -> plus#(times(x,plus(y,times(|1|(),|0|()))),x) p2: times#(x,plus(y,|1|())) -> times#(x,plus(y,times(|1|(),|0|()))) p3: times#(x,plus(y,|1|())) -> plus#(y,times(|1|(),|0|())) p4: times#(x,plus(y,|1|())) -> times#(|1|(),|0|()) p5: plus#(s(x),s(y)) -> plus#(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))) p6: plus#(s(x),s(y)) -> if#(gt(x,y),x,y) p7: plus#(s(x),s(y)) -> gt#(x,y) p8: plus#(s(x),s(y)) -> if#(not(gt(x,y)),id(x),id(y)) p9: plus#(s(x),s(y)) -> not#(gt(x,y)) p10: plus#(s(x),s(y)) -> id#(x) p11: plus#(s(x),s(y)) -> id#(y) p12: plus#(s(x),x) -> plus#(if(gt(x,x),id(x),id(x)),s(x)) p13: plus#(s(x),x) -> if#(gt(x,x),id(x),id(x)) p14: plus#(s(x),x) -> gt#(x,x) p15: plus#(s(x),x) -> id#(x) p16: plus#(id(x),s(y)) -> plus#(x,if(gt(s(y),y),y,s(y))) p17: plus#(id(x),s(y)) -> if#(gt(s(y),y),y,s(y)) p18: plus#(id(x),s(y)) -> gt#(s(y),y) p19: not#(x) -> if#(x,false(),true()) p20: gt#(s(x),s(y)) -> gt#(x,y) and R consists of: r1: times(x,plus(y,|1|())) -> plus(times(x,plus(y,times(|1|(),|0|()))),x) r2: times(x,|1|()) -> x r3: times(x,|0|()) -> |0|() r4: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r5: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r6: plus(zero(),y) -> y r7: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r8: id(x) -> x r9: if(true(),x,y) -> x r10: if(false(),x,y) -> y r11: not(x) -> if(x,false(),true()) r12: gt(s(x),zero()) -> true() r13: gt(zero(),y) -> false() r14: gt(s(x),s(y)) -> gt(x,y) The estimated dependency graph contains the following SCCs: {p2} {p5, p12, p16} {p20} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: times#(x,plus(y,|1|())) -> times#(x,plus(y,times(|1|(),|0|()))) and R consists of: r1: times(x,plus(y,|1|())) -> plus(times(x,plus(y,times(|1|(),|0|()))),x) r2: times(x,|1|()) -> x r3: times(x,|0|()) -> |0|() r4: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r5: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r6: plus(zero(),y) -> y r7: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r8: id(x) -> x r9: if(true(),x,y) -> x r10: if(false(),x,y) -> y r11: not(x) -> if(x,false(),true()) r12: gt(s(x),zero()) -> true() r13: gt(zero(),y) -> false() r14: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of r3, r4, r5, r6, r7, r8, r9, r10, r11, r12, r13, r14 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: times#_A(x1,x2) = x1 + x2 + 4 plus_A(x1,x2) = x2 + 1 |1|_A() = 5 times_A(x1,x2) = x2 + 1 |0|_A() = 1 s_A(x1) = 0 if_A(x1,x2,x3) = x2 + x3 + 3 gt_A(x1,x2) = 3 not_A(x1) = x1 + 5 id_A(x1) = x1 + 2 zero_A() = 2 true_A() = 0 false_A() = 1 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: times#_A(x1,x2) = max{0, x1 - 1, x2 - 35} plus_A(x1,x2) = max{97, x1 + 28, x2 + 28} |1|_A = 8 times_A(x1,x2) = 68 |0|_A = 68 s_A(x1) = max{8, x1} if_A(x1,x2,x3) = max{19, x1 - 13, x2, x3} gt_A(x1,x2) = max{21, x1 - 11, x2 - 15} not_A(x1) = max{19, x1 - 2} id_A(x1) = max{6, x1} zero_A = 10 true_A = 0 false_A = 19 times#!_A(x1,x2) = max{1, x2 - 3} plus!_A(x1,x2) = 0 |1|!_A = 94 times!_A(x1,x2) = max{95, x1 + 87, x2 - 28} |0|!_A = 88 s!_A(x1) = max{1, x1 - 98} if!_A(x1,x2,x3) = max{x2 - 7, x3 + 25} gt!_A(x1,x2) = 13 not!_A(x1) = max{26, x1 + 11} id!_A(x1) = max{0, x1 - 99} zero!_A = 11 true!_A = 12 false!_A = 14 partial status: pi(times#) = [1] pi(plus) = [] pi(|1|) = [] pi(times) = [2] pi(|0|) = [] pi(s) = [] pi(if) = [] pi(gt) = [] pi(not) = [1] pi(id) = [] pi(zero) = [] pi(true) = [] pi(false) = [] 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: 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: times(x,plus(y,|1|())) -> plus(times(x,plus(y,times(|1|(),|0|()))),x) r2: times(x,|1|()) -> x r3: times(x,|0|()) -> |0|() r4: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r5: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r6: plus(zero(),y) -> y r7: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r8: id(x) -> x r9: if(true(),x,y) -> x r10: if(false(),x,y) -> y r11: not(x) -> if(x,false(),true()) r12: gt(s(x),zero()) -> true() r13: gt(zero(),y) -> false() r14: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of r8, r9, r10 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: plus#_A(x1,x2) = 7 s_A(x1) = x1 if_A(x1,x2,x3) = x2 + x3 gt_A(x1,x2) = x1 + 6 not_A(x1) = x1 + 2 id_A(x1) = x1 true_A() = 5 false_A() = 3 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: plus#_A(x1,x2) = max{x1, x2} s_A(x1) = x1 + 8 if_A(x1,x2,x3) = max{3, x2, x3} gt_A(x1,x2) = max{x1, x2} not_A(x1) = x1 id_A(x1) = x1 + 3 true_A = 35 false_A = 3 plus#!_A(x1,x2) = max{x1 + 30, x2 + 26} s!_A(x1) = max{40, x1 + 16} if!_A(x1,x2,x3) = max{41, x2 - 4, x3 - 9} gt!_A(x1,x2) = max{47, x1 - 9, x2 + 39} not!_A(x1) = max{25, x1 - 2} id!_A(x1) = max{40, x1 + 39} true!_A = 41 false!_A = 40 partial status: pi(plus#) = [] pi(s) = [] pi(if) = [2, 3] pi(gt) = [] pi(not) = [1] pi(id) = [1] pi(true) = [] pi(false) = [] The following rules are removed: p1, p3 -- 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: times(x,plus(y,|1|())) -> plus(times(x,plus(y,times(|1|(),|0|()))),x) r2: times(x,|1|()) -> x r3: times(x,|0|()) -> |0|() r4: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r5: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r6: plus(zero(),y) -> y r7: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r8: id(x) -> x r9: if(true(),x,y) -> x r10: if(false(),x,y) -> y r11: not(x) -> if(x,false(),true()) r12: gt(s(x),zero()) -> true() r13: gt(zero(),y) -> false() r14: 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: times(x,plus(y,|1|())) -> plus(times(x,plus(y,times(|1|(),|0|()))),x) r2: times(x,|1|()) -> x r3: times(x,|0|()) -> |0|() r4: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r5: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r6: plus(zero(),y) -> y r7: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r8: id(x) -> x r9: if(true(),x,y) -> x r10: if(false(),x,y) -> y r11: not(x) -> if(x,false(),true()) r12: gt(s(x),zero()) -> true() r13: gt(zero(),y) -> false() r14: gt(s(x),s(y)) -> gt(x,y) The set of usable rules consists of r9, r10, r12, r13, r14 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: plus#_A(x1,x2) = x1 + 7 id_A(x1) = x1 + 9 s_A(x1) = 6 if_A(x1,x2,x3) = x2 + x3 + 2 gt_A(x1,x2) = 2 true_A() = 1 false_A() = 1 zero_A() = 2 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: plus#_A(x1,x2) = max{0, x1 - 19, x2 - 9} id_A(x1) = x1 + 7 s_A(x1) = max{8, x1} if_A(x1,x2,x3) = max{1, x1 - 1, x2, x3} gt_A(x1,x2) = max{1, x1 - 9, x2 - 9} true_A = 1 false_A = 1 zero_A = 8 plus#!_A(x1,x2) = max{2, x1 - 19, x2 - 14} id!_A(x1) = x1 + 1 s!_A(x1) = max{28, x1 + 19} if!_A(x1,x2,x3) = max{3, x1 - 16, x2 - 15, x3 - 10} gt!_A(x1,x2) = max{29, x1 - 13, x2 - 9} true!_A = 20 false!_A = 0 zero!_A = 21 partial status: pi(plus#) = [] pi(id) = [1] pi(s) = [] pi(if) = [] 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: times(x,plus(y,|1|())) -> plus(times(x,plus(y,times(|1|(),|0|()))),x) r2: times(x,|1|()) -> x r3: times(x,|0|()) -> |0|() r4: plus(s(x),s(y)) -> s(s(plus(if(gt(x,y),x,y),if(not(gt(x,y)),id(x),id(y))))) r5: plus(s(x),x) -> plus(if(gt(x,x),id(x),id(x)),s(x)) r6: plus(zero(),y) -> y r7: plus(id(x),s(y)) -> s(plus(x,if(gt(s(y),y),y,s(y)))) r8: id(x) -> x r9: if(true(),x,y) -> x r10: if(false(),x,y) -> y r11: not(x) -> if(x,false(),true()) r12: gt(s(x),zero()) -> true() r13: gt(zero(),y) -> false() r14: 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: matrix interpretation with standard point-wise order: carrier: N^1 order: standard order interpretations: gt#_A(x1,x2) = 8 s_A(x1) = 7 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: gt#_A(x1,x2) = max{0, x1 - 2, x2 - 2} s_A(x1) = max{263, x1 + 1} gt#!_A(x1,x2) = x2 + 7 s!_A(x1) = x1 + 7 partial status: pi(gt#) = [] pi(s) = [] The following rules are removed: p1 Then no dependency pair remains.