YES Proof: This system is quasi-decreasing. By \cite{O02}, p. 214, Proposition 7.2.50. This system is of type 3 or smaller. This system is deterministic. System R transformed to U(R). Call external tool: ttt2 - trs 30 Input: ?2(s(y), x, y) -> x ?1(y, x, y) -> ?2(g(g(x)), x, y) f(x, y) -> ?1(g(x), x, y) ?4(x, x, y) -> y ?3(s(x), x, y) -> ?4(g(g(y)), x, y) f(x, y) -> ?3(g(y), x, y) DP Processor: DPs: ?1#(y,x,y) -> ?2#(g(g(x)),x,y) f#(x,y) -> ?1#(g(x),x,y) ?3#(s(x),x,y) -> ?4#(g(g(y)),x,y) f#(x,y) -> ?3#(g(y),x,y) TRS: ?2(s(y),x,y) -> x ?1(y,x,y) -> ?2(g(g(x)),x,y) f(x,y) -> ?1(g(x),x,y) ?4(x,x,y) -> y ?3(s(x),x,y) -> ?4(g(g(y)),x,y) f(x,y) -> ?3(g(y),x,y) TDG Processor: DPs: ?1#(y,x,y) -> ?2#(g(g(x)),x,y) f#(x,y) -> ?1#(g(x),x,y) ?3#(s(x),x,y) -> ?4#(g(g(y)),x,y) f#(x,y) -> ?3#(g(y),x,y) TRS: ?2(s(y),x,y) -> x ?1(y,x,y) -> ?2(g(g(x)),x,y) f(x,y) -> ?1(g(x),x,y) ?4(x,x,y) -> y ?3(s(x),x,y) -> ?4(g(g(y)),x,y) f(x,y) -> ?3(g(y),x,y) graph: f#(x,y) -> ?3#(g(y),x,y) -> ?3#(s(x),x,y) -> ?4#(g(g(y)),x,y) f#(x,y) -> ?1#(g(x),x,y) -> ?1#(y,x,y) -> ?2#(g(g(x)),x,y) SCC Processor: #sccs: 0 #rules: 0 #arcs: 2/16