YES We show the termination of the TRS R: f(x,y) -> g(x,y) g(h(x),y) -> h(f(x,y)) g(h(x),y) -> h(g(x,y)) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: f#(x,y) -> g#(x,y) p2: g#(h(x),y) -> f#(x,y) p3: g#(h(x),y) -> g#(x,y) and R consists of: r1: f(x,y) -> g(x,y) r2: g(h(x),y) -> h(f(x,y)) r3: g(h(x),y) -> h(g(x,y)) 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: f#(x,y) -> g#(x,y) p2: g#(h(x),y) -> g#(x,y) p3: g#(h(x),y) -> f#(x,y) and R consists of: r1: f(x,y) -> g(x,y) r2: g(h(x),y) -> h(f(x,y)) r3: g(h(x),y) -> h(g(x,y)) 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: f#_A(x1,x2) = ((1,0),(1,0)) x1 + x2 + (4,3) g#_A(x1,x2) = ((1,0),(1,0)) x1 + x2 + (3,2) h_A(x1) = ((1,0),(0,0)) x1 + (2,1) precedence: f# = g# = h partial status: pi(f#) = [] pi(g#) = [2] pi(h) = [] 2. weighted path order base order: matrix interpretations: carrier: N^2 order: lexicographic order interpretations: f#_A(x1,x2) = (0,0) g#_A(x1,x2) = (0,0) h_A(x1) = (1,1) precedence: h > f# = g# partial status: pi(f#) = [] pi(g#) = [] pi(h) = [] The next rules are strictly ordered: p1, p2 We remove them from the problem. -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: g#(h(x),y) -> f#(x,y) and R consists of: r1: f(x,y) -> g(x,y) r2: g(h(x),y) -> h(f(x,y)) r3: g(h(x),y) -> h(g(x,y)) The estimated dependency graph contains the following SCCs: (no SCCs)