YES We show the termination of the TRS R: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) a__f(s(|0|())) -> a__f(a__p(s(|0|()))) a__p(s(X)) -> mark(X) mark(f(X)) -> a__f(mark(X)) mark(p(X)) -> a__p(mark(X)) mark(|0|()) -> |0|() mark(cons(X1,X2)) -> cons(mark(X1),X2) mark(s(X)) -> s(mark(X)) a__f(X) -> f(X) a__p(X) -> p(X) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(s(|0|())) -> a__f#(a__p(s(|0|()))) p2: a__f#(s(|0|())) -> a__p#(s(|0|())) p3: a__p#(s(X)) -> mark#(X) p4: mark#(f(X)) -> a__f#(mark(X)) p5: mark#(f(X)) -> mark#(X) p6: mark#(p(X)) -> a__p#(mark(X)) p7: mark#(p(X)) -> mark#(X) p8: mark#(cons(X1,X2)) -> mark#(X1) p9: mark#(s(X)) -> mark#(X) and R consists of: r1: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) r2: a__f(s(|0|())) -> a__f(a__p(s(|0|()))) r3: a__p(s(X)) -> mark(X) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(p(X)) -> a__p(mark(X)) r6: mark(|0|()) -> |0|() r7: mark(cons(X1,X2)) -> cons(mark(X1),X2) r8: mark(s(X)) -> s(mark(X)) r9: a__f(X) -> f(X) r10: a__p(X) -> p(X) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p5, p6, p7, p8, p9} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(s(|0|())) -> a__f#(a__p(s(|0|()))) p2: a__f#(s(|0|())) -> a__p#(s(|0|())) p3: a__p#(s(X)) -> mark#(X) p4: mark#(s(X)) -> mark#(X) p5: mark#(cons(X1,X2)) -> mark#(X1) p6: mark#(p(X)) -> mark#(X) p7: mark#(p(X)) -> a__p#(mark(X)) p8: mark#(f(X)) -> mark#(X) p9: mark#(f(X)) -> a__f#(mark(X)) and R consists of: r1: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) r2: a__f(s(|0|())) -> a__f(a__p(s(|0|()))) r3: a__p(s(X)) -> mark(X) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(p(X)) -> a__p(mark(X)) r6: mark(|0|()) -> |0|() r7: mark(cons(X1,X2)) -> cons(mark(X1),X2) r8: mark(s(X)) -> s(mark(X)) r9: a__f(X) -> f(X) r10: a__p(X) -> p(X) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: a__f#_A(x1) = (10,1) s_A(x1) = x1 + (8,0) |0|_A() = (1,5) a__p_A(x1) = ((1,0),(0,0)) x1 + (0,2) a__p#_A(x1) = ((1,0),(1,1)) x1 + (0,1) mark#_A(x1) = ((1,0),(0,0)) x1 + (8,8) cons_A(x1,x2) = x1 + (1,1) p_A(x1) = ((1,0),(0,0)) x1 + (0,1) mark_A(x1) = ((1,0),(1,1)) x1 + (3,3) f_A(x1) = ((1,0),(0,0)) x1 + (2,4) a__f_A(x1) = ((1,0),(0,0)) x1 + (2,7) precedence: |0| = a__p = mark > a__f > cons > a__f# > s = a__p# = mark# = p = f partial status: pi(a__f#) = [] pi(s) = [1] pi(|0|) = [] pi(a__p) = [] pi(a__p#) = [1] pi(mark#) = [] pi(cons) = [1] pi(p) = [] pi(mark) = [1] pi(f) = [] pi(a__f) = [] 2. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: a__f#_A(x1) = (4,2) s_A(x1) = (1,7) |0|_A() = (2,10) a__p_A(x1) = (3,11) a__p#_A(x1) = (5,1) mark#_A(x1) = (6,3) cons_A(x1,x2) = (1,1) p_A(x1) = (0,6) mark_A(x1) = x1 + (3,5) f_A(x1) = (7,4) a__f_A(x1) = (7,8) precedence: a__p = mark > a__f > s = |0| = cons > mark# = f > a__f# > a__p# = p partial status: pi(a__f#) = [] pi(s) = [] pi(|0|) = [] pi(a__p) = [] pi(a__p#) = [] pi(mark#) = [] pi(cons) = [] pi(p) = [] pi(mark) = [] pi(f) = [] pi(a__f) = [] The next rules are strictly ordered: p2, p3, p7, p9 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(s(|0|())) -> a__f#(a__p(s(|0|()))) p2: mark#(s(X)) -> mark#(X) p3: mark#(cons(X1,X2)) -> mark#(X1) p4: mark#(p(X)) -> mark#(X) p5: mark#(f(X)) -> mark#(X) and R consists of: r1: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) r2: a__f(s(|0|())) -> a__f(a__p(s(|0|()))) r3: a__p(s(X)) -> mark(X) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(p(X)) -> a__p(mark(X)) r6: mark(|0|()) -> |0|() r7: mark(cons(X1,X2)) -> cons(mark(X1),X2) r8: mark(s(X)) -> s(mark(X)) r9: a__f(X) -> f(X) r10: a__p(X) -> p(X) The estimated dependency graph contains the following SCCs: {p1} {p2, p3, p4, p5} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(s(|0|())) -> a__f#(a__p(s(|0|()))) and R consists of: r1: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) r2: a__f(s(|0|())) -> a__f(a__p(s(|0|()))) r3: a__p(s(X)) -> mark(X) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(p(X)) -> a__p(mark(X)) r6: mark(|0|()) -> |0|() r7: mark(cons(X1,X2)) -> cons(mark(X1),X2) r8: mark(s(X)) -> s(mark(X)) r9: a__f(X) -> f(X) r10: a__p(X) -> p(X) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10 Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: a__f#_A(x1) = x1 s_A(x1) = ((1,0),(0,0)) x1 + (3,3) |0|_A() = (2,2) a__p_A(x1) = ((1,0),(0,0)) x1 + (0,3) a__f_A(x1) = x1 cons_A(x1,x2) = (1,1) f_A(x1) = x1 mark_A(x1) = ((1,0),(1,1)) x1 + (2,4) p_A(x1) = ((1,0),(0,0)) x1 + (0,2) precedence: s > |0| > a__f# = a__p = cons = mark > a__f > f = p partial status: pi(a__f#) = [1] pi(s) = [] pi(|0|) = [] pi(a__p) = [] pi(a__f) = [1] pi(cons) = [] pi(f) = [1] pi(mark) = [1] pi(p) = [] 2. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: a__f#_A(x1) = (10,4) s_A(x1) = (9,3) |0|_A() = (11,7) a__p_A(x1) = (8,2) a__f_A(x1) = (7,6) cons_A(x1,x2) = (7,3) f_A(x1) = (6,5) mark_A(x1) = ((1,0),(0,0)) x1 + (5,4) p_A(x1) = (4,1) precedence: mark > cons > a__p > p > |0| > a__f# = s = a__f > f partial status: pi(a__f#) = [] pi(s) = [] pi(|0|) = [] pi(a__p) = [] pi(a__f) = [] pi(cons) = [] pi(f) = [] pi(mark) = [] pi(p) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: mark#(s(X)) -> mark#(X) p2: mark#(f(X)) -> mark#(X) p3: mark#(p(X)) -> mark#(X) p4: mark#(cons(X1,X2)) -> mark#(X1) and R consists of: r1: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) r2: a__f(s(|0|())) -> a__f(a__p(s(|0|()))) r3: a__p(s(X)) -> mark(X) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(p(X)) -> a__p(mark(X)) r6: mark(|0|()) -> |0|() r7: mark(cons(X1,X2)) -> cons(mark(X1),X2) r8: mark(s(X)) -> s(mark(X)) r9: a__f(X) -> f(X) r10: a__p(X) -> p(X) The set of usable rules consists of (no rules) Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: mark#_A(x1) = ((1,0),(1,0)) x1 + (1,2) s_A(x1) = ((1,0),(1,1)) x1 + (2,3) f_A(x1) = x1 + (2,1) p_A(x1) = x1 cons_A(x1,x2) = x1 + x2 + (2,1) precedence: f = p = cons > mark# = s partial status: pi(mark#) = [] pi(s) = [1] pi(f) = [1] pi(p) = [1] pi(cons) = [2] 2. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: mark#_A(x1) = (0,0) s_A(x1) = (1,1) f_A(x1) = ((1,0),(0,0)) x1 + (1,1) p_A(x1) = ((1,0),(0,0)) x1 + (1,1) cons_A(x1,x2) = x2 + (1,1) precedence: mark# = s = f = p = cons partial status: pi(mark#) = [] pi(s) = [] pi(f) = [] pi(p) = [] pi(cons) = [] The next rules are strictly ordered: p1, p2, p4 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: mark#(p(X)) -> mark#(X) and R consists of: r1: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) r2: a__f(s(|0|())) -> a__f(a__p(s(|0|()))) r3: a__p(s(X)) -> mark(X) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(p(X)) -> a__p(mark(X)) r6: mark(|0|()) -> |0|() r7: mark(cons(X1,X2)) -> cons(mark(X1),X2) r8: mark(s(X)) -> s(mark(X)) r9: a__f(X) -> f(X) r10: a__p(X) -> p(X) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: mark#(p(X)) -> mark#(X) and R consists of: r1: a__f(|0|()) -> cons(|0|(),f(s(|0|()))) r2: a__f(s(|0|())) -> a__f(a__p(s(|0|()))) r3: a__p(s(X)) -> mark(X) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(p(X)) -> a__p(mark(X)) r6: mark(|0|()) -> |0|() r7: mark(cons(X1,X2)) -> cons(mark(X1),X2) r8: mark(s(X)) -> s(mark(X)) r9: a__f(X) -> f(X) r10: a__p(X) -> p(X) The set of usable rules consists of (no rules) Take the reduction pair: lexicographic combination of reduction pairs: 1. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: mark#_A(x1) = ((1,0),(1,1)) x1 + (2,2) p_A(x1) = ((1,0),(0,0)) x1 + (1,1) precedence: mark# = p partial status: pi(mark#) = [] pi(p) = [] 2. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: mark#_A(x1) = ((1,0),(0,0)) x1 p_A(x1) = (1,1) precedence: p > mark# partial status: pi(mark#) = [] pi(p) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.