Consider the TRS R consisting of the rewrite rules 1: minus(X,0) -> X 2: minus(s(X),s(Y)) -> p(minus(X,Y)) 3: p(s(X)) -> X 4: div(0,s(Y)) -> 0 5: div(s(X),s(Y)) -> s(div(minus(X,Y),s(Y))) There are 4 dependency pairs: 6: MINUS(s(X),s(Y)) -> P(minus(X,Y)) 7: MINUS(s(X),s(Y)) -> MINUS(X,Y) 8: DIV(s(X),s(Y)) -> DIV(minus(X,Y),s(Y)) 9: DIV(s(X),s(Y)) -> MINUS(X,Y) The approximated dependency graph contains 2 SCCs: {7} and {8}. - Consider the SCC {7}. There are no usable rules. By taking the polynomial interpretation [s](x) = x + 1 and [MINUS](x,y) = x + y + 1, rule 7 is strictly decreasing. - Consider the SCC {8}. The usable rules are {1-3}. By taking the polynomial interpretation [0] = 1, [minus](x,y) = x, [p](x) = [s](x) = x + 1 and [DIV](x,y) = x + y + 1, the rules in {1,2} are weakly decreasing and the rules in {3,8} are strictly decreasing. Hence the TRS is terminating.