YES We show the termination of the TRS R: b(x,y) -> c(a(c(y),a(|0|(),x))) a(y,x) -> y a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: b#(x,y) -> a#(c(y),a(|0|(),x)) p2: b#(x,y) -> a#(|0|(),x) p3: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(a(c(b(|0|(),y)),x),|0|()) p4: a#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) p5: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(|0|(),y) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) 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: b#(x,y) -> a#(c(y),a(|0|(),x)) p2: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(|0|(),y) p3: b#(x,y) -> a#(|0|(),x) p4: a#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) p5: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(a(c(b(|0|(),y)),x),|0|()) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) 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: standard order interpretations: b#_A(x1,x2) = ((0,1),(0,1)) x1 + ((1,1),(1,1)) x2 + (60,65) a#_A(x1,x2) = ((1,1),(1,1)) x1 + ((0,1),(0,1)) x2 + (40,46) c_A(x1) = ((0,0),(1,0)) x1 + (1,1) a_A(x1,x2) = ((1,0),(1,1)) x1 + ((0,1),(0,1)) x2 + (10,1) |0|_A() = (15,1) b_A(x1,x2) = ((1,1),(1,1)) x1 + ((1,0),(0,0)) x2 + (8,29) precedence: a > b > |0| > c > b# = a# partial status: pi(b#) = [] pi(a#) = [] pi(c) = [] pi(a) = [] pi(|0|) = [] pi(b) = [1] The next rules are strictly ordered: p5 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: b#(x,y) -> a#(c(y),a(|0|(),x)) p2: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(|0|(),y) p3: b#(x,y) -> a#(|0|(),x) p4: a#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) The estimated dependency graph contains the following SCCs: {p1, p2, p3, p4} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: b#(x,y) -> a#(c(y),a(|0|(),x)) p2: a#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) p3: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(|0|(),y) p4: b#(x,y) -> a#(|0|(),x) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) 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: standard order interpretations: b#_A(x1,x2) = ((1,0),(0,0)) x1 + ((1,1),(0,0)) x2 + (42,0) a#_A(x1,x2) = ((1,1),(0,0)) x1 + ((1,0),(0,0)) x2 + (24,0) c_A(x1) = ((0,1),(0,0)) x1 + (1,1) a_A(x1,x2) = ((1,1),(0,1)) x1 + ((1,0),(1,0)) x2 + (2,1) |0|_A() = (2,11) b_A(x1,x2) = ((1,0),(1,0)) x1 + ((0,0),(0,1)) x2 + (20,11) precedence: b# > a > b > |0| > a# = c partial status: pi(b#) = [] pi(a#) = [] pi(c) = [] pi(a) = [1] pi(|0|) = [] pi(b) = [] 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#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) p2: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(|0|(),y) p3: b#(x,y) -> a#(|0|(),x) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) The estimated dependency graph contains the following SCCs: {p1, p2, p3} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) p2: a#(y,c(b(a(|0|(),x),|0|()))) -> b#(|0|(),y) p3: b#(x,y) -> a#(|0|(),x) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) 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: standard order interpretations: a#_A(x1,x2) = ((1,1),(0,1)) x2 + (1,10) c_A(x1) = ((0,0),(1,0)) x1 + (2,1) b_A(x1,x2) = ((1,1),(1,1)) x1 + x2 + (3,16) a_A(x1,x2) = ((1,0),(1,1)) x1 + ((0,1),(1,1)) x2 + (1,0) |0|_A() = (9,0) b#_A(x1,x2) = ((1,1),(0,1)) x1 + (2,33) precedence: a# = c = b = a > |0| = b# partial status: pi(a#) = [] pi(c) = [] pi(b) = [] pi(a) = [] pi(|0|) = [] pi(b#) = [] 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#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) p2: b#(x,y) -> a#(|0|(),x) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) The estimated dependency graph contains the following SCCs: {p1} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: a#(y,c(b(a(|0|(),x),|0|()))) -> a#(c(b(|0|(),y)),x) and R consists of: r1: b(x,y) -> c(a(c(y),a(|0|(),x))) r2: a(y,x) -> y r3: a(y,c(b(a(|0|(),x),|0|()))) -> b(a(c(b(|0|(),y)),x),|0|()) 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: standard order interpretations: a#_A(x1,x2) = ((1,0),(0,0)) x2 + (84,2) c_A(x1) = ((0,1),(0,0)) x1 + (1,3) b_A(x1,x2) = x1 + ((0,1),(1,0)) x2 + (46,27) a_A(x1,x2) = ((1,0),(1,1)) x1 + ((1,0),(1,0)) x2 + (10,4) |0|_A() = (26,1) precedence: a > a# = |0| > c = b partial status: pi(a#) = [] pi(c) = [] pi(b) = [] pi(a) = [] pi(|0|) = [] The next rules are strictly ordered: p1 We remove them from the problem. Then no dependency pair remains.