Input TRS: 1: plus(s(s(x)),y) -> s(plus(x,s(y))) 2: plus(x,s(s(y))) -> s(plus(s(x),y)) 3: plus(s(0()),y) -> s(y) 4: plus(0(),y) -> y 5: ack(0(),y) -> s(y) 6: ack(s(x),0()) -> ack(x,s(0())) 7: ack(s(x),s(y)) -> ack(x,plus(y,ack(s(x),y))) Number of strict rules: 7 Direct Order(PosReal,>,Poly) ... failed. Freezing ack 1: plus(s(s(x)),y) -> s(plus(x,s(y))) 2: plus(x,s(s(y))) -> s(plus(s(x),y)) 3: plus(s(0()),y) -> s(y) 4: plus(0(),y) -> y 5: ack❆1_0(y) -> s(y) 6: ack❆1_s(x,0()) -> ack(x,s(0())) 7: ack❆1_s(x,s(y)) -> ack(x,plus(y,ack❆1_s(x,y))) 8: ack(0(),_1) ->= ack❆1_0(_1) 9: ack(s(_1),_2) ->= ack❆1_s(_1,_2) Number of strict rules: 7 Direct Order(PosReal,>,Poly) ... failed. Dependency Pairs: #1: #plus(x,s(s(y))) -> #plus(s(x),y) #2: #ack❆1_s(x,0()) -> #ack(x,s(0())) #3: #ack(s(_1),_2) ->? #ack❆1_s(_1,_2) #4: #ack❆1_s(x,s(y)) -> #ack(x,plus(y,ack❆1_s(x,y))) #5: #ack❆1_s(x,s(y)) -> #plus(y,ack❆1_s(x,y)) #6: #ack❆1_s(x,s(y)) -> #ack❆1_s(x,y) #7: #plus(s(s(x)),y) -> #plus(x,s(y)) #8: #ack(0(),_1) ->? #ack❆1_0(_1) Number of SCCs: 2, DPs: 6, edges: 12 SCC { #1 #7 } Removing DPs: Order(PosReal,>,Sum)... succeeded. s(x1) weight: (/ 1 4) + x1 ack(x1,x2) weight: 0 #plus(x1,x2) weight: x1 + x2 #ack❆1_0(x1) weight: 0 0() weight: 0 ack❆1_0(x1) weight: 0 plus(x1,x2) weight: 0 #ack(x1,x2) weight: 0 ack❆1_s(x1,x2) weight: 0 #ack❆1_s(x1,x2) weight: 0 Usable rules: { } Removed DPs: #1 #7 Number of SCCs: 1, DPs: 4, edges: 8 SCC { #2..4 #6 } Removing DPs: Order(PosReal,>,Sum)... succeeded. s(x1) weight: (/ 1 4) + x1 ack(x1,x2) weight: x1 #plus(x1,x2) weight: 0 #ack❆1_0(x1) weight: 0 0() weight: 0 ack❆1_0(x1) weight: (/ 1 8) + x1 plus(x1,x2) weight: (/ 1 8) + x2 #ack(x1,x2) weight: x1 ack❆1_s(x1,x2) weight: (/ 3 8) #ack❆1_s(x1,x2) weight: (/ 1 8) + x1 Usable rules: { } Removed DPs: #2..4 Number of SCCs: 1, DPs: 1, edges: 1 SCC { #6 } Removing DPs: Order(PosReal,>,Sum)... succeeded. s(x1) weight: (/ 1 4) + x1 ack(x1,x2) weight: x1 #plus(x1,x2) weight: 0 #ack❆1_0(x1) weight: 0 0() weight: 0 ack❆1_0(x1) weight: (/ 1 8) + x1 plus(x1,x2) weight: (/ 1 8) + x2 #ack(x1,x2) weight: 0 ack❆1_s(x1,x2) weight: (/ 3 8) #ack❆1_s(x1,x2) weight: (/ 1 8) + x2 Usable rules: { } Removed DPs: #6 Number of SCCs: 0, DPs: 0, edges: 0 YES