YES We show the termination of the TRS R: h(f(x),y) -> f(g(x,y)) g(x,y) -> h(x,y) -- SCC decomposition. Consider the dependency pair problem (P, R), where P consists of p1: h#(f(x),y) -> g#(x,y) p2: g#(x,y) -> h#(x,y) and R consists of: r1: h(f(x),y) -> f(g(x,y)) r2: g(x,y) -> h(x,y) The estimated dependency graph contains the following SCCs: {p1, p2} -- Reduction pair. Consider the dependency pair problem (P, R), where P consists of p1: h#(f(x),y) -> g#(x,y) p2: g#(x,y) -> h#(x,y) and R consists of: r1: h(f(x),y) -> f(g(x,y)) r2: g(x,y) -> h(x,y) The set of usable rules consists of (no rules) Take the reduction pair: matrix interpretations: carrier: N^4 order: lexicographic order interpretations: h#_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,0,1,0)) x1 + ((0,0,0,0),(1,0,0,0),(0,0,0,0),(0,0,0,0)) x2 f_A(x1) = ((1,0,0,0),(1,1,0,0),(1,1,1,0),(1,1,1,1)) x1 + (0,0,2,1) g#_A(x1,x2) = ((1,0,0,0),(0,1,0,0),(0,0,1,0),(0,1,1,0)) x1 + ((0,0,0,0),(1,0,0,0),(0,0,0,0),(0,0,0,0)) x2 + (0,0,1,1) The next rules are strictly ordered: p1, p2 We remove them from the problem. Then no dependency pair remains.