YES We show the termination of the relative TRS R/S: R: f(|0|()) -> true() f(|1|()) -> false() f(s(x)) -> f(x) if(true(),s(x),s(y)) -> s(x) if(false(),s(x),s(y)) -> s(y) g(x,c(y)) -> c(g(x,y)) g(x,c(y)) -> g(x,if(f(x),c(g(s(x),y)),c(y))) S: rand(x) -> x rand(x) -> rand(s(x)) -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: f#(s(x)) -> f#(x) p2: g#(x,c(y)) -> g#(x,y) p3: g#(x,c(y)) -> g#(x,if(f(x),c(g(s(x),y)),c(y))) p4: g#(x,c(y)) -> if#(f(x),c(g(s(x),y)),c(y)) p5: g#(x,c(y)) -> f#(x) p6: g#(x,c(y)) -> g#(s(x),y) and R consists of: r1: f(|0|()) -> true() r2: f(|1|()) -> false() r3: f(s(x)) -> f(x) r4: if(true(),s(x),s(y)) -> s(x) r5: if(false(),s(x),s(y)) -> s(y) r6: g(x,c(y)) -> c(g(x,y)) r7: g(x,c(y)) -> g(x,if(f(x),c(g(s(x),y)),c(y))) r8: rand(x) -> x r9: rand(x) -> rand(s(x)) The estimated dependency graph contains the following SCCs: {p2, p6} {p1} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: g#(x,c(y)) -> g#(s(x),y) p2: g#(x,c(y)) -> g#(x,y) and R consists of: r1: f(|0|()) -> true() r2: f(|1|()) -> false() r3: f(s(x)) -> f(x) r4: if(true(),s(x),s(y)) -> s(x) r5: if(false(),s(x),s(y)) -> s(y) r6: g(x,c(y)) -> c(g(x,y)) r7: g(x,c(y)) -> g(x,if(f(x),c(g(s(x),y)),c(y))) r8: rand(x) -> x r9: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: g#_A(x1,x2) = x2 + (0,1) c_A(x1) = x1 + (2,0) s_A(x1) = (0,3) f_A(x1) = (5,5) |0|_A() = (2,1) true_A() = (1,4) |1|_A() = (2,1) false_A() = (1,6) if_A(x1,x2,x3) = (1,4) g_A(x1,x2) = ((1,0),(1,0)) x2 + (2,0) rand_A(x1) = ((1,0),(1,0)) x1 + (1,4) precedence: |0| = |1| = rand > true > g# = if > s = f = false > g > c partial status: pi(g#) = [2] pi(c) = [1] pi(s) = [] pi(f) = [] pi(|0|) = [] pi(true) = [] pi(|1|) = [] pi(false) = [] pi(if) = [] pi(g) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. -- SCC decomposition. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: g#(x,c(y)) -> g#(x,y) and R consists of: r1: f(|0|()) -> true() r2: f(|1|()) -> false() r3: f(s(x)) -> f(x) r4: if(true(),s(x),s(y)) -> s(x) r5: if(false(),s(x),s(y)) -> s(y) r6: g(x,c(y)) -> c(g(x,y)) r7: g(x,c(y)) -> g(x,if(f(x),c(g(s(x),y)),c(y))) r8: rand(x) -> x r9: rand(x) -> rand(s(x)) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: g#(x,c(y)) -> g#(x,y) and R consists of: r1: f(|0|()) -> true() r2: f(|1|()) -> false() r3: f(s(x)) -> f(x) r4: if(true(),s(x),s(y)) -> s(x) r5: if(false(),s(x),s(y)) -> s(y) r6: g(x,c(y)) -> c(g(x,y)) r7: g(x,c(y)) -> g(x,if(f(x),c(g(s(x),y)),c(y))) r8: rand(x) -> x r9: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: g#_A(x1,x2) = x1 + ((1,0),(1,1)) x2 + (3,5) c_A(x1) = ((1,0),(0,0)) x1 + (2,4) f_A(x1) = (4,6) |0|_A() = (2,4) true_A() = (1,3) |1|_A() = (2,1) false_A() = (1,5) s_A(x1) = (0,2) if_A(x1,x2,x3) = ((1,0),(0,0)) x3 + (0,3) g_A(x1,x2) = ((1,0),(0,0)) x2 + (1,5) rand_A(x1) = ((1,0),(1,0)) x1 + (1,1) precedence: f = |0| = true = |1| = rand > false > g# > s = if > c = g partial status: pi(g#) = [1] pi(c) = [] pi(f) = [] pi(|0|) = [] pi(true) = [] pi(|1|) = [] pi(false) = [] pi(s) = [] pi(if) = [] pi(g) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains. -- Reduction pair. Consider the non-minimal dependency pair problem (P, R), where P consists of p1: f#(s(x)) -> f#(x) and R consists of: r1: f(|0|()) -> true() r2: f(|1|()) -> false() r3: f(s(x)) -> f(x) r4: if(true(),s(x),s(y)) -> s(x) r5: if(false(),s(x),s(y)) -> s(y) r6: g(x,c(y)) -> c(g(x,y)) r7: g(x,c(y)) -> g(x,if(f(x),c(g(s(x),y)),c(y))) r8: rand(x) -> x r9: rand(x) -> rand(s(x)) The set of usable rules consists of r1, r2, r3, r4, r5, r6, r7, r8, r9 Take the reduction pair: weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: f#_A(x1) = x1 + (0,3) s_A(x1) = x1 + (0,4) f_A(x1) = (2,6) |0|_A() = (2,6) true_A() = (1,5) |1|_A() = (2,1) false_A() = (1,7) if_A(x1,x2,x3) = ((1,0),(0,0)) x2 + ((1,0),(0,0)) x3 + (1,2) g_A(x1,x2) = (8,1) c_A(x1) = (3,3) rand_A(x1) = ((1,0),(0,0)) x1 + (1,5) precedence: true = |1| = false = rand > f# > |0| > f = g = c > s = if partial status: pi(f#) = [1] pi(s) = [] pi(f) = [] pi(|0|) = [] pi(true) = [] pi(|1|) = [] pi(false) = [] pi(if) = [] pi(g) = [] pi(c) = [] pi(rand) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.