MAYBE * Step 1: DependencyPairs MAYBE + Considered Problem: - Strict TRS: div(x,y) -> if1(ge(x,y),x,y) ge(x,0()) -> true() ge(0(),s(x)) -> false() ge(s(x),s(y)) -> ge(x,y) gt(0(),y) -> false() gt(s(x),0()) -> true() gt(s(x),s(y)) -> gt(x,y) if(false(),x,y) -> 0() if(true(),x,y) -> s(minus(p(x),y)) if1(false(),x,y) -> 0() if1(true(),x,y) -> if2(gt(y,0()),x,y) if2(false(),x,y) -> 0() if2(true(),x,y) -> s(div(minus(x,y),y)) minus(x,y) -> if(gt(x,y),x,y) p(0()) -> 0() p(s(x)) -> x - Signature: {div/2,ge/2,gt/2,if/3,if1/3,if2/3,minus/2,p/1} / {0/0,false/0,s/1,true/0} - Obligation: innermost runtime complexity wrt. defined symbols {div,ge,gt,if,if1,if2,minus,p} and constructors {0,false,s ,true} + Applied Processor: DependencyPairs {dpKind_ = DT} + Details: We add the following dependency tuples: Strict DPs div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) ge#(x,0()) -> c_2() ge#(0(),s(x)) -> c_3() ge#(s(x),s(y)) -> c_4(ge#(x,y)) gt#(0(),y) -> c_5() gt#(s(x),0()) -> c_6() gt#(s(x),s(y)) -> c_7(gt#(x,y)) if#(false(),x,y) -> c_8() if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) if1#(false(),x,y) -> c_10() if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) if2#(false(),x,y) -> c_12() if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) p#(0()) -> c_15() p#(s(x)) -> c_16() Weak DPs and mark the set of starting terms. * Step 2: UsableRules MAYBE + Considered Problem: - Strict DPs: div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) ge#(x,0()) -> c_2() ge#(0(),s(x)) -> c_3() ge#(s(x),s(y)) -> c_4(ge#(x,y)) gt#(0(),y) -> c_5() gt#(s(x),0()) -> c_6() gt#(s(x),s(y)) -> c_7(gt#(x,y)) if#(false(),x,y) -> c_8() if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) if1#(false(),x,y) -> c_10() if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) if2#(false(),x,y) -> c_12() if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) p#(0()) -> c_15() p#(s(x)) -> c_16() - Weak TRS: div(x,y) -> if1(ge(x,y),x,y) ge(x,0()) -> true() ge(0(),s(x)) -> false() ge(s(x),s(y)) -> ge(x,y) gt(0(),y) -> false() gt(s(x),0()) -> true() gt(s(x),s(y)) -> gt(x,y) if(false(),x,y) -> 0() if(true(),x,y) -> s(minus(p(x),y)) if1(false(),x,y) -> 0() if1(true(),x,y) -> if2(gt(y,0()),x,y) if2(false(),x,y) -> 0() if2(true(),x,y) -> s(div(minus(x,y),y)) minus(x,y) -> if(gt(x,y),x,y) p(0()) -> 0() p(s(x)) -> x - Signature: {div/2,ge/2,gt/2,if/3,if1/3,if2/3,minus/2,p/1,div#/2,ge#/2,gt#/2,if#/3,if1#/3,if2#/3,minus#/2,p#/1} / {0/0 ,false/0,s/1,true/0,c_1/2,c_2/0,c_3/0,c_4/1,c_5/0,c_6/0,c_7/1,c_8/0,c_9/2,c_10/0,c_11/2,c_12/0,c_13/2,c_14/2 ,c_15/0,c_16/0} - Obligation: innermost runtime complexity wrt. defined symbols {div#,ge#,gt#,if#,if1#,if2#,minus#,p#} and constructors {0 ,false,s,true} + Applied Processor: UsableRules + Details: We replace rewrite rules by usable rules: ge(x,0()) -> true() ge(0(),s(x)) -> false() ge(s(x),s(y)) -> ge(x,y) gt(0(),y) -> false() gt(s(x),0()) -> true() gt(s(x),s(y)) -> gt(x,y) if(false(),x,y) -> 0() if(true(),x,y) -> s(minus(p(x),y)) minus(x,y) -> if(gt(x,y),x,y) p(0()) -> 0() p(s(x)) -> x div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) ge#(x,0()) -> c_2() ge#(0(),s(x)) -> c_3() ge#(s(x),s(y)) -> c_4(ge#(x,y)) gt#(0(),y) -> c_5() gt#(s(x),0()) -> c_6() gt#(s(x),s(y)) -> c_7(gt#(x,y)) if#(false(),x,y) -> c_8() if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) if1#(false(),x,y) -> c_10() if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) if2#(false(),x,y) -> c_12() if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) p#(0()) -> c_15() p#(s(x)) -> c_16() * Step 3: PredecessorEstimation MAYBE + Considered Problem: - Strict DPs: div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) ge#(x,0()) -> c_2() ge#(0(),s(x)) -> c_3() ge#(s(x),s(y)) -> c_4(ge#(x,y)) gt#(0(),y) -> c_5() gt#(s(x),0()) -> c_6() gt#(s(x),s(y)) -> c_7(gt#(x,y)) if#(false(),x,y) -> c_8() if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) if1#(false(),x,y) -> c_10() if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) if2#(false(),x,y) -> c_12() if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) p#(0()) -> c_15() p#(s(x)) -> c_16() - Weak TRS: ge(x,0()) -> true() ge(0(),s(x)) -> false() ge(s(x),s(y)) -> ge(x,y) gt(0(),y) -> false() gt(s(x),0()) -> true() gt(s(x),s(y)) -> gt(x,y) if(false(),x,y) -> 0() if(true(),x,y) -> s(minus(p(x),y)) minus(x,y) -> if(gt(x,y),x,y) p(0()) -> 0() p(s(x)) -> x - Signature: {div/2,ge/2,gt/2,if/3,if1/3,if2/3,minus/2,p/1,div#/2,ge#/2,gt#/2,if#/3,if1#/3,if2#/3,minus#/2,p#/1} / {0/0 ,false/0,s/1,true/0,c_1/2,c_2/0,c_3/0,c_4/1,c_5/0,c_6/0,c_7/1,c_8/0,c_9/2,c_10/0,c_11/2,c_12/0,c_13/2,c_14/2 ,c_15/0,c_16/0} - Obligation: innermost runtime complexity wrt. defined symbols {div#,ge#,gt#,if#,if1#,if2#,minus#,p#} and constructors {0 ,false,s,true} + Applied Processor: PredecessorEstimation {onSelection = all simple predecessor estimation selector} + Details: We estimate the number of application of {2,3,5,6,8,10,12,15,16} by application of Pre({2,3,5,6,8,10,12,15,16}) = {1,4,7,9,11,14}. Here rules are labelled as follows: 1: div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) 2: ge#(x,0()) -> c_2() 3: ge#(0(),s(x)) -> c_3() 4: ge#(s(x),s(y)) -> c_4(ge#(x,y)) 5: gt#(0(),y) -> c_5() 6: gt#(s(x),0()) -> c_6() 7: gt#(s(x),s(y)) -> c_7(gt#(x,y)) 8: if#(false(),x,y) -> c_8() 9: if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) 10: if1#(false(),x,y) -> c_10() 11: if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) 12: if2#(false(),x,y) -> c_12() 13: if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) 14: minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) 15: p#(0()) -> c_15() 16: p#(s(x)) -> c_16() * Step 4: RemoveWeakSuffixes MAYBE + Considered Problem: - Strict DPs: div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) ge#(s(x),s(y)) -> c_4(ge#(x,y)) gt#(s(x),s(y)) -> c_7(gt#(x,y)) if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) - Weak DPs: ge#(x,0()) -> c_2() ge#(0(),s(x)) -> c_3() gt#(0(),y) -> c_5() gt#(s(x),0()) -> c_6() if#(false(),x,y) -> c_8() if1#(false(),x,y) -> c_10() if2#(false(),x,y) -> c_12() p#(0()) -> c_15() p#(s(x)) -> c_16() - Weak TRS: ge(x,0()) -> true() ge(0(),s(x)) -> false() ge(s(x),s(y)) -> ge(x,y) gt(0(),y) -> false() gt(s(x),0()) -> true() gt(s(x),s(y)) -> gt(x,y) if(false(),x,y) -> 0() if(true(),x,y) -> s(minus(p(x),y)) minus(x,y) -> if(gt(x,y),x,y) p(0()) -> 0() p(s(x)) -> x - Signature: {div/2,ge/2,gt/2,if/3,if1/3,if2/3,minus/2,p/1,div#/2,ge#/2,gt#/2,if#/3,if1#/3,if2#/3,minus#/2,p#/1} / {0/0 ,false/0,s/1,true/0,c_1/2,c_2/0,c_3/0,c_4/1,c_5/0,c_6/0,c_7/1,c_8/0,c_9/2,c_10/0,c_11/2,c_12/0,c_13/2,c_14/2 ,c_15/0,c_16/0} - Obligation: innermost runtime complexity wrt. defined symbols {div#,ge#,gt#,if#,if1#,if2#,minus#,p#} and constructors {0 ,false,s,true} + Applied Processor: RemoveWeakSuffixes + Details: Consider the dependency graph 1:S:div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) -->_1 if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())):5 -->_2 ge#(s(x),s(y)) -> c_4(ge#(x,y)):2 -->_1 if1#(false(),x,y) -> c_10():13 -->_2 ge#(0(),s(x)) -> c_3():9 -->_2 ge#(x,0()) -> c_2():8 2:S:ge#(s(x),s(y)) -> c_4(ge#(x,y)) -->_1 ge#(0(),s(x)) -> c_3():9 -->_1 ge#(x,0()) -> c_2():8 -->_1 ge#(s(x),s(y)) -> c_4(ge#(x,y)):2 3:S:gt#(s(x),s(y)) -> c_7(gt#(x,y)) -->_1 gt#(s(x),0()) -> c_6():11 -->_1 gt#(0(),y) -> c_5():10 -->_1 gt#(s(x),s(y)) -> c_7(gt#(x,y)):3 4:S:if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) -->_1 minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)):7 -->_2 p#(s(x)) -> c_16():16 -->_2 p#(0()) -> c_15():15 5:S:if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) -->_1 if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)):6 -->_1 if2#(false(),x,y) -> c_12():14 -->_2 gt#(s(x),0()) -> c_6():11 -->_2 gt#(0(),y) -> c_5():10 6:S:if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) -->_2 minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)):7 -->_1 div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)):1 7:S:minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) -->_1 if#(false(),x,y) -> c_8():12 -->_2 gt#(s(x),0()) -> c_6():11 -->_2 gt#(0(),y) -> c_5():10 -->_1 if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)):4 -->_2 gt#(s(x),s(y)) -> c_7(gt#(x,y)):3 8:W:ge#(x,0()) -> c_2() 9:W:ge#(0(),s(x)) -> c_3() 10:W:gt#(0(),y) -> c_5() 11:W:gt#(s(x),0()) -> c_6() 12:W:if#(false(),x,y) -> c_8() 13:W:if1#(false(),x,y) -> c_10() 14:W:if2#(false(),x,y) -> c_12() 15:W:p#(0()) -> c_15() 16:W:p#(s(x)) -> c_16() The following weak DPs constitute a sub-graph of the DG that is closed under successors. The DPs are removed. 13: if1#(false(),x,y) -> c_10() 8: ge#(x,0()) -> c_2() 9: ge#(0(),s(x)) -> c_3() 14: if2#(false(),x,y) -> c_12() 15: p#(0()) -> c_15() 16: p#(s(x)) -> c_16() 10: gt#(0(),y) -> c_5() 11: gt#(s(x),0()) -> c_6() 12: if#(false(),x,y) -> c_8() * Step 5: SimplifyRHS MAYBE + Considered Problem: - Strict DPs: div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) ge#(s(x),s(y)) -> c_4(ge#(x,y)) gt#(s(x),s(y)) -> c_7(gt#(x,y)) if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) - Weak TRS: ge(x,0()) -> true() ge(0(),s(x)) -> false() ge(s(x),s(y)) -> ge(x,y) gt(0(),y) -> false() gt(s(x),0()) -> true() gt(s(x),s(y)) -> gt(x,y) if(false(),x,y) -> 0() if(true(),x,y) -> s(minus(p(x),y)) minus(x,y) -> if(gt(x,y),x,y) p(0()) -> 0() p(s(x)) -> x - Signature: {div/2,ge/2,gt/2,if/3,if1/3,if2/3,minus/2,p/1,div#/2,ge#/2,gt#/2,if#/3,if1#/3,if2#/3,minus#/2,p#/1} / {0/0 ,false/0,s/1,true/0,c_1/2,c_2/0,c_3/0,c_4/1,c_5/0,c_6/0,c_7/1,c_8/0,c_9/2,c_10/0,c_11/2,c_12/0,c_13/2,c_14/2 ,c_15/0,c_16/0} - Obligation: innermost runtime complexity wrt. defined symbols {div#,ge#,gt#,if#,if1#,if2#,minus#,p#} and constructors {0 ,false,s,true} + Applied Processor: SimplifyRHS + Details: Consider the dependency graph 1:S:div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) -->_1 if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())):5 -->_2 ge#(s(x),s(y)) -> c_4(ge#(x,y)):2 2:S:ge#(s(x),s(y)) -> c_4(ge#(x,y)) -->_1 ge#(s(x),s(y)) -> c_4(ge#(x,y)):2 3:S:gt#(s(x),s(y)) -> c_7(gt#(x,y)) -->_1 gt#(s(x),s(y)) -> c_7(gt#(x,y)):3 4:S:if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)) -->_1 minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)):7 5:S:if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y),gt#(y,0())) -->_1 if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)):6 6:S:if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) -->_2 minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)):7 -->_1 div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)):1 7:S:minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) -->_1 if#(true(),x,y) -> c_9(minus#(p(x),y),p#(x)):4 -->_2 gt#(s(x),s(y)) -> c_7(gt#(x,y)):3 Due to missing edges in the depndency graph, the right-hand sides of following rules could be simplified: if#(true(),x,y) -> c_9(minus#(p(x),y)) if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y)) * Step 6: Failure MAYBE + Considered Problem: - Strict DPs: div#(x,y) -> c_1(if1#(ge(x,y),x,y),ge#(x,y)) ge#(s(x),s(y)) -> c_4(ge#(x,y)) gt#(s(x),s(y)) -> c_7(gt#(x,y)) if#(true(),x,y) -> c_9(minus#(p(x),y)) if1#(true(),x,y) -> c_11(if2#(gt(y,0()),x,y)) if2#(true(),x,y) -> c_13(div#(minus(x,y),y),minus#(x,y)) minus#(x,y) -> c_14(if#(gt(x,y),x,y),gt#(x,y)) - Weak TRS: ge(x,0()) -> true() ge(0(),s(x)) -> false() ge(s(x),s(y)) -> ge(x,y) gt(0(),y) -> false() gt(s(x),0()) -> true() gt(s(x),s(y)) -> gt(x,y) if(false(),x,y) -> 0() if(true(),x,y) -> s(minus(p(x),y)) minus(x,y) -> if(gt(x,y),x,y) p(0()) -> 0() p(s(x)) -> x - Signature: {div/2,ge/2,gt/2,if/3,if1/3,if2/3,minus/2,p/1,div#/2,ge#/2,gt#/2,if#/3,if1#/3,if2#/3,minus#/2,p#/1} / {0/0 ,false/0,s/1,true/0,c_1/2,c_2/0,c_3/0,c_4/1,c_5/0,c_6/0,c_7/1,c_8/0,c_9/1,c_10/0,c_11/1,c_12/0,c_13/2,c_14/2 ,c_15/0,c_16/0} - Obligation: innermost runtime complexity wrt. defined symbols {div#,ge#,gt#,if#,if1#,if2#,minus#,p#} and constructors {0 ,false,s,true} + Applied Processor: EmptyProcessor + Details: The problem is still open. MAYBE