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)) mod(|0|(),y) -> |0|() mod(s(x),|0|()) -> |0|() mod(s(x),s(y)) -> if_mod(le(y,x),s(x),s(y)) if_mod(true(),s(x),s(y)) -> mod(minus(x,y),s(y)) if_mod(false(),s(x),s(y)) -> s(x) -- 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: mod#(s(x),s(y)) -> if_mod#(le(y,x),s(x),s(y)) p6: mod#(s(x),s(y)) -> le#(y,x) p7: if_mod#(true(),s(x),s(y)) -> mod#(minus(x,y),s(y)) p8: if_mod#(true(),s(x),s(y)) -> minus#(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: mod(|0|(),y) -> |0|() r9: mod(s(x),|0|()) -> |0|() r10: mod(s(x),s(y)) -> if_mod(le(y,x),s(x),s(y)) r11: if_mod(true(),s(x),s(y)) -> mod(minus(x,y),s(y)) r12: if_mod(false(),s(x),s(y)) -> s(x) The estimated dependency graph contains the following SCCs: {p5, p7} {p2, p4} {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: if_mod#(true(),s(x),s(y)) -> mod#(minus(x,y),s(y)) p2: mod#(s(x),s(y)) -> if_mod#(le(y,x),s(x),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: mod(|0|(),y) -> |0|() r9: mod(s(x),|0|()) -> |0|() r10: mod(s(x),s(y)) -> if_mod(le(y,x),s(x),s(y)) r11: if_mod(true(),s(x),s(y)) -> mod(minus(x,y),s(y)) r12: if_mod(false(),s(x),s(y)) -> s(x) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: if_mod#_A(x1,x2,x3) = max{17, x1 - 8, x2 + 13, x3 - 12} true_A = 25 s_A(x1) = 11 mod#_A(x1,x2) = max{x1 + 8, x2 + 13} minus_A(x1,x2) = 16 le_A(x1,x2) = 26 |0|_A = 13 false_A = 12 if_minus_A(x1,x2,x3) = max{12, x1 - 11} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: if_mod#_A(x1,x2,x3) = max{11, x3 - 19} true_A = 27 s_A(x1) = x1 + 29 mod#_A(x1,x2) = max{11, x2 - 19} minus_A(x1,x2) = x1 + 28 le_A(x1,x2) = x2 + 27 |0|_A = 49 false_A = 1 if_minus_A(x1,x2,x3) = max{49, x2 + 28} if_mod#!_A(x1,x2,x3) = max{24, x1 - 1, x2 - 3} true!_A = 0 s!_A(x1) = 23 mod#!_A(x1,x2) = max{25, x1 - 2} minus!_A(x1,x2) = 21 le!_A(x1,x2) = 19 |0|!_A = 31 false!_A = 20 if_minus!_A(x1,x2,x3) = x1 + 23 partial status: pi(if_mod#) = [] pi(true) = [] pi(s) = [] pi(mod#) = [] pi(minus) = [] pi(le) = [] pi(|0|) = [] pi(false) = [] pi(if_minus) = [] The following rules are removed: p2 -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: if_mod#(true(),s(x),s(y)) -> mod#(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: mod(|0|(),y) -> |0|() r9: mod(s(x),|0|()) -> |0|() r10: mod(s(x),s(y)) -> if_mod(le(y,x),s(x),s(y)) r11: if_mod(true(),s(x),s(y)) -> mod(minus(x,y),s(y)) r12: if_mod(false(),s(x),s(y)) -> s(x) The estimated dependency graph contains the following SCCs: (no SCCs) -- 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: mod(|0|(),y) -> |0|() r9: mod(s(x),|0|()) -> |0|() r10: mod(s(x),s(y)) -> if_mod(le(y,x),s(x),s(y)) r11: if_mod(true(),s(x),s(y)) -> mod(minus(x,y),s(y)) r12: if_mod(false(),s(x),s(y)) -> s(x) The set of usable rules consists of r1, r2, r3, r4 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: if_minus#_A(x1,x2,x3) = max{13, x1 - 8, x2 + 1, x3 - 22} false_A = 1 s_A(x1) = max{11, x1 + 5} minus#_A(x1,x2) = max{13, x1 + 1, x2 - 22} le_A(x1,x2) = max{7, x1 - 24, x2 - 23} |0|_A = 2 true_A = 3 minus_A(x1,x2) = max{8, x1 - 17, x2 - 22} base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: if_minus#_A(x1,x2,x3) = max{0, x1 - 21, x2 - 34, x3 - 24} false_A = 2 s_A(x1) = max{19, x1 + 10} minus#_A(x1,x2) = max{0, x1 - 34, x2 - 24} le_A(x1,x2) = max{20, x1 - 21, x2 - 3} |0|_A = 2 true_A = 0 minus_A(x1,x2) = max{15, x1 - 34, x2 - 25} if_minus#!_A(x1,x2,x3) = max{x1 - 42, x2 - 52, x3 + 3} false!_A = 1 s!_A(x1) = max{4, x1 - 43} minus#!_A(x1,x2) = max{x1 - 42, x2 + 3} le!_A(x1,x2) = max{2, x1 - 63, x2 - 71} |0|!_A = 6 true!_A = 7 minus!_A(x1,x2) = max{8, x1 - 55, x2 - 70} partial status: pi(if_minus#) = [2] pi(false) = [] pi(s) = [] pi(minus#) = [1] pi(le) = [] pi(|0|) = [] pi(true) = [] pi(minus) = [] 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: mod(|0|(),y) -> |0|() r9: mod(s(x),|0|()) -> |0|() r10: mod(s(x),s(y)) -> if_mod(le(y,x),s(x),s(y)) r11: if_mod(true(),s(x),s(y)) -> mod(minus(x,y),s(y)) r12: if_mod(false(),s(x),s(y)) -> s(x) 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: mod(|0|(),y) -> |0|() r9: mod(s(x),|0|()) -> |0|() r10: mod(s(x),s(y)) -> if_mod(le(y,x),s(x),s(y)) r11: if_mod(true(),s(x),s(y)) -> mod(minus(x,y),s(y)) r12: if_mod(false(),s(x),s(y)) -> s(x) The set of usable rules consists of r2 Take the reduction pair: generalized weighted path order (>=MG, >G) base order 1: max/plus interpretation on natural numbers: le#_A(x1,x2) = max{8, x1} s_A(x1) = x1 + 8 le_A(x1,x2) = max{14, x1 - 9, x2 - 9} |0|_A = 3 false_A = 1 base order 2: marked-algebra reduction triple (>=A, >=A!, >A!): max/plus interpretation on natural numbers: le#_A(x1,x2) = 0 s_A(x1) = max{2, x1 - 12} le_A(x1,x2) = max{0, x1 - 5, x2 - 1} |0|_A = 9 false_A = 1 le#!_A(x1,x2) = max{15, x1 + 13} s!_A(x1) = max{28, x1 + 14} le!_A(x1,x2) = max{29, x1 - 10, x2 - 10} |0|!_A = 25 false!_A = 23 partial status: pi(le#) = [1] pi(s) = [] pi(le) = [] pi(|0|) = [] pi(false) = [] The following rules are removed: p1 Then no dependency pair remains.