YES We show the termination of the TRS R: a__f(X) -> a__if(mark(X),c(),f(true())) a__if(true(),X,Y) -> mark(X) a__if(false(),X,Y) -> mark(Y) mark(f(X)) -> a__f(mark(X)) mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) mark(c()) -> c() mark(true()) -> true() mark(false()) -> false() a__f(X) -> f(X) a__if(X1,X2,X3) -> if(X1,X2,X3) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(X) -> a__if#(mark(X),c(),f(true())) p2: a__f#(X) -> mark#(X) p3: a__if#(true(),X,Y) -> mark#(X) p4: a__if#(false(),X,Y) -> mark#(Y) p5: mark#(f(X)) -> a__f#(mark(X)) p6: mark#(f(X)) -> mark#(X) p7: mark#(if(X1,X2,X3)) -> a__if#(mark(X1),mark(X2),X3) p8: mark#(if(X1,X2,X3)) -> mark#(X1) p9: mark#(if(X1,X2,X3)) -> mark#(X2) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) 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#(X) -> a__if#(mark(X),c(),f(true())) p2: a__if#(false(),X,Y) -> mark#(Y) p3: mark#(if(X1,X2,X3)) -> mark#(X2) p4: mark#(if(X1,X2,X3)) -> mark#(X1) p5: mark#(if(X1,X2,X3)) -> a__if#(mark(X1),mark(X2),X3) p6: a__if#(true(),X,Y) -> mark#(X) p7: mark#(f(X)) -> mark#(X) p8: mark#(f(X)) -> a__f#(mark(X)) p9: a__f#(X) -> mark#(X) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: a__f#_A(x1) = ((1,0),(1,1)) x1 + (1,2) a__if#_A(x1,x2,x3) = x1 + x2 + x3 + (1,2) mark_A(x1) = x1 c_A() = (0,0) f_A(x1) = ((1,0),(1,1)) x1 true_A() = (0,0) false_A() = (0,1) mark#_A(x1) = x1 + (1,2) if_A(x1,x2,x3) = ((1,0),(1,1)) x1 + ((1,0),(1,1)) x2 + ((1,0),(1,1)) x3 a__f_A(x1) = ((1,0),(1,1)) x1 a__if_A(x1,x2,x3) = ((1,0),(1,1)) x1 + ((1,0),(1,1)) x2 + ((1,0),(1,1)) x3 precedence: a__f# = a__if# = mark# > mark = c = f = true = false = if = a__f = a__if partial status: pi(a__f#) = [] pi(a__if#) = [] pi(mark) = [] pi(c) = [] pi(f) = [] pi(true) = [] pi(false) = [] pi(mark#) = [] pi(if) = [] pi(a__f) = [] pi(a__if) = [] The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(X) -> a__if#(mark(X),c(),f(true())) p2: mark#(if(X1,X2,X3)) -> mark#(X2) p3: mark#(if(X1,X2,X3)) -> mark#(X1) p4: mark#(if(X1,X2,X3)) -> a__if#(mark(X1),mark(X2),X3) p5: a__if#(true(),X,Y) -> mark#(X) p6: mark#(f(X)) -> mark#(X) p7: mark#(f(X)) -> a__f#(mark(X)) p8: a__f#(X) -> mark#(X) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4, p5, p6, p7, p8} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(X) -> a__if#(mark(X),c(),f(true())) p2: a__if#(true(),X,Y) -> mark#(X) p3: mark#(f(X)) -> a__f#(mark(X)) p4: a__f#(X) -> mark#(X) p5: mark#(f(X)) -> mark#(X) p6: mark#(if(X1,X2,X3)) -> a__if#(mark(X1),mark(X2),X3) p7: mark#(if(X1,X2,X3)) -> mark#(X1) p8: mark#(if(X1,X2,X3)) -> mark#(X2) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: a__f#_A(x1) = x1 + (1,8) a__if#_A(x1,x2,x3) = x1 + x2 + ((0,0),(1,0)) x3 + (0,2) mark_A(x1) = x1 c_A() = (0,1) f_A(x1) = x1 + (2,4) true_A() = (0,2) mark#_A(x1) = x1 + (0,3) if_A(x1,x2,x3) = x1 + ((1,0),(1,1)) x2 + ((1,0),(1,0)) x3 a__f_A(x1) = x1 + (2,4) a__if_A(x1,x2,x3) = x1 + ((1,0),(1,1)) x2 + ((1,0),(1,0)) x3 false_A() = (1,1) precedence: mark = if = a__f = a__if > c = true = false > f > a__f# = a__if# > mark# partial status: pi(a__f#) = [1] pi(a__if#) = [] pi(mark) = [] pi(c) = [] pi(f) = [1] pi(true) = [] pi(mark#) = [1] pi(if) = [] pi(a__f) = [] pi(a__if) = [] pi(false) = [] The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: a__f#(X) -> a__if#(mark(X),c(),f(true())) p2: mark#(f(X)) -> a__f#(mark(X)) p3: a__f#(X) -> mark#(X) p4: mark#(f(X)) -> mark#(X) p5: mark#(if(X1,X2,X3)) -> a__if#(mark(X1),mark(X2),X3) p6: mark#(if(X1,X2,X3)) -> mark#(X1) p7: mark#(if(X1,X2,X3)) -> mark#(X2) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The estimated dependency graph contains the following SCCs: {p2, p3, p4, p6, p7} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: mark#(f(X)) -> a__f#(mark(X)) p2: a__f#(X) -> mark#(X) p3: mark#(if(X1,X2,X3)) -> mark#(X2) p4: mark#(if(X1,X2,X3)) -> mark#(X1) p5: mark#(f(X)) -> mark#(X) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9, r10 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: mark#_A(x1) = x1 f_A(x1) = x1 + (0,3) a__f#_A(x1) = x1 + (0,1) mark_A(x1) = x1 if_A(x1,x2,x3) = x1 + ((1,0),(1,1)) x2 + ((1,0),(0,0)) x3 + (0,1) a__f_A(x1) = x1 + (0,3) a__if_A(x1,x2,x3) = x1 + ((1,0),(1,1)) x2 + ((1,0),(0,0)) x3 + (0,1) c_A() = (0,1) true_A() = (0,1) false_A() = (1,1) precedence: mark = a__f = a__if = c > f = if > mark# > a__f# = true > false partial status: pi(mark#) = [1] pi(f) = [1] pi(a__f#) = [] pi(mark) = [] pi(if) = [1, 2] pi(a__f) = [] pi(a__if) = [] pi(c) = [] pi(true) = [] 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: a__f#(X) -> mark#(X) p2: mark#(if(X1,X2,X3)) -> mark#(X2) p3: mark#(if(X1,X2,X3)) -> mark#(X1) p4: mark#(f(X)) -> mark#(X) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The estimated dependency graph contains the following SCCs: {p2, p3, p4} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: mark#(if(X1,X2,X3)) -> mark#(X2) p2: mark#(f(X)) -> mark#(X) p3: mark#(if(X1,X2,X3)) -> mark#(X1) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) 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: mark#_A(x1) = ((1,0),(0,0)) x1 + (2,2) if_A(x1,x2,x3) = ((1,0),(0,0)) x1 + x2 + x3 + (1,3) f_A(x1) = x1 + (1,1) precedence: mark# = f > if partial status: pi(mark#) = [] pi(if) = [2] pi(f) = [] The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: mark#(if(X1,X2,X3)) -> mark#(X2) p2: mark#(if(X1,X2,X3)) -> mark#(X1) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: mark#(if(X1,X2,X3)) -> mark#(X2) p2: mark#(if(X1,X2,X3)) -> mark#(X1) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The set of usable rules consists of (no rules) Take the monotone reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: mark#_A(x1) = ((1,0),(1,1)) x1 + (1,2) if_A(x1,x2,x3) = x1 + x2 + x3 + (2,1) precedence: mark# > if partial status: pi(mark#) = [1] pi(if) = [1, 2, 3] The next rules are strictly ordered: p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: mark#(if(X1,X2,X3)) -> mark#(X2) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: mark#(if(X1,X2,X3)) -> mark#(X2) and R consists of: r1: a__f(X) -> a__if(mark(X),c(),f(true())) r2: a__if(true(),X,Y) -> mark(X) r3: a__if(false(),X,Y) -> mark(Y) r4: mark(f(X)) -> a__f(mark(X)) r5: mark(if(X1,X2,X3)) -> a__if(mark(X1),mark(X2),X3) r6: mark(c()) -> c() r7: mark(true()) -> true() r8: mark(false()) -> false() r9: a__f(X) -> f(X) r10: a__if(X1,X2,X3) -> if(X1,X2,X3) 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: mark#_A(x1) = ((1,0),(1,1)) x1 + (1,2) if_A(x1,x2,x3) = ((1,0),(1,1)) x1 + ((1,0),(1,1)) x2 + ((1,0),(1,1)) x3 + (2,1) precedence: mark# > if partial status: pi(mark#) = [1] pi(if) = [2, 3] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.