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)) gcd(|0|(),y) -> y gcd(s(x),|0|()) -> s(x) gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),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: gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) p6: gcd#(s(x),s(y)) -> le#(y,x) p7: if_gcd#(true(),s(x),s(y)) -> gcd#(minus(x,y),s(y)) p8: if_gcd#(true(),s(x),s(y)) -> minus#(x,y) p9: if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) p10: if_gcd#(false(),s(x),s(y)) -> minus#(y,x) 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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) The estimated dependency graph contains the following SCCs: {p5, p7, p9} {p2, p4} {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: if_gcd#(false(),s(x),s(y)) -> gcd#(minus(y,x),s(x)) p2: gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) p3: if_gcd#(true(),s(x),s(y)) -> gcd#(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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: if_gcd#_A(x1,x2,x3) = x2 + ((1,0),(0,0)) x3 + (0,1) false_A() = (2,6) s_A(x1) = ((1,0),(0,0)) x1 + (8,5) gcd#_A(x1,x2) = ((1,0),(1,0)) x1 + ((1,0),(0,0)) x2 + (1,1) minus_A(x1,x2) = ((1,0),(0,0)) x1 + ((0,0),(1,0)) x2 + (3,0) le_A(x1,x2) = ((0,0),(1,0)) x2 + (2,0) true_A() = (1,6) if_minus_A(x1,x2,x3) = x1 + ((1,0),(0,0)) x2 + (1,0) |0|_A() = (7,0) precedence: if_gcd# > gcd# > s = minus = if_minus > true > le > false = |0| partial status: pi(if_gcd#) = [2] pi(false) = [] pi(s) = [] pi(gcd#) = [] pi(minus) = [] pi(le) = [] pi(true) = [] pi(if_minus) = [] pi(|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: gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) p2: if_gcd#(true(),s(x),s(y)) -> gcd#(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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: gcd#(s(x),s(y)) -> if_gcd#(le(y,x),s(x),s(y)) p2: if_gcd#(true(),s(x),s(y)) -> gcd#(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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: gcd#_A(x1,x2) = ((0,0),(1,0)) x1 + (8,4) s_A(x1) = ((1,0),(0,0)) x1 + (7,12) if_gcd#_A(x1,x2,x3) = ((0,0),(1,0)) x1 + ((0,0),(1,0)) x2 + (8,1) le_A(x1,x2) = ((0,0),(1,0)) x1 + (2,10) true_A() = (1,9) minus_A(x1,x2) = x1 + (2,4) if_minus_A(x1,x2,x3) = ((1,0),(0,0)) x2 + (2,15) |0|_A() = (0,14) false_A() = (0,13) precedence: le = true = minus = if_minus = |0| > gcd# = s = if_gcd# > false partial status: pi(gcd#) = [] pi(s) = [] pi(if_gcd#) = [] pi(le) = [] pi(true) = [] pi(minus) = [] pi(if_minus) = [] pi(|0|) = [] pi(false) = [] 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: if_gcd#(true(),s(x),s(y)) -> gcd#(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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) The set of usable rules consists of r1, r2, r3 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: if_minus#_A(x1,x2,x3) = x2 false_A() = (4,0) s_A(x1) = ((1,0),(1,1)) x1 + (3,2) minus#_A(x1,x2) = x1 + (1,1) le_A(x1,x2) = ((1,0),(1,1)) x2 + (2,0) |0|_A() = (5,1) true_A() = (1,0) precedence: if_minus# = s > minus# = le = |0| > false = true partial status: pi(if_minus#) = [] pi(false) = [] pi(s) = [1] pi(minus#) = [1] pi(le) = [] pi(|0|) = [] pi(true) = [] 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: 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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),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: gcd(|0|(),y) -> y r9: gcd(s(x),|0|()) -> s(x) r10: gcd(s(x),s(y)) -> if_gcd(le(y,x),s(x),s(y)) r11: if_gcd(true(),s(x),s(y)) -> gcd(minus(x,y),s(y)) r12: if_gcd(false(),s(x),s(y)) -> gcd(minus(y,x),s(x)) The set of usable rules consists of (no rules) Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: le#_A(x1,x2) = x1 s_A(x1) = x1 + (1,1) precedence: s > le# partial status: pi(le#) = [] pi(s) = [1] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.