YES Problem: not(x) -> if(x,false(),true()) and(x,y) -> if(x,y,false()) or(x,y) -> if(x,true(),y) implies(x,y) -> if(x,y,true()) =(x,x) -> true() =(x,y) -> if(x,y,not(y)) if(true(),x,y) -> x if(false(),x,y) -> y if(x,x,if(x,false(),true())) -> true() =(x,y) -> if(x,y,if(y,false(),true())) Proof: DP Processor: DPs: not#(x) -> if#(x,false(),true()) and#(x,y) -> if#(x,y,false()) or#(x,y) -> if#(x,true(),y) implies#(x,y) -> if#(x,y,true()) =#(x,y) -> not#(y) =#(x,y) -> if#(x,y,not(y)) =#(x,y) -> if#(y,false(),true()) =#(x,y) -> if#(x,y,if(y,false(),true())) TRS: not(x) -> if(x,false(),true()) and(x,y) -> if(x,y,false()) or(x,y) -> if(x,true(),y) implies(x,y) -> if(x,y,true()) =(x,x) -> true() =(x,y) -> if(x,y,not(y)) if(true(),x,y) -> x if(false(),x,y) -> y if(x,x,if(x,false(),true())) -> true() =(x,y) -> if(x,y,if(y,false(),true())) Arctic Interpretation Processor: dimension: 1 interpretation: [=#](x0, x1) = x0 + 8x1 + 7, [implies#](x0, x1) = x0 + x1 + 4, [or#](x0, x1) = x0 + 2x1 + 3, [and#](x0, x1) = x0 + x1 + 3, [if#](x0, x1, x2) = 1x2 + 2, [not#](x0) = 4, [=](x0, x1) = 4x0 + 13x1 + 7, [implies](x0, x1) = 4x0 + 2x1 + 4, [or](x0, x1) = 4x0 + 2x1 + 4, [and](x0, x1) = 4x0 + 8x1 + 3, [if](x0, x1, x2) = 3x0 + 1x1 + 1x2 + 2, [true] = 2, [false] = 0, [not](x0) = 4x0 + 5 orientation: not#(x) = 4 >= 3 = if#(x,false(),true()) and#(x,y) = x + y + 3 >= 2 = if#(x,y,false()) or#(x,y) = x + 2y + 3 >= 1y + 2 = if#(x,true(),y) implies#(x,y) = x + y + 4 >= 3 = if#(x,y,true()) =#(x,y) = x + 8y + 7 >= 4 = not#(y) =#(x,y) = x + 8y + 7 >= 5y + 6 = if#(x,y,not(y)) =#(x,y) = x + 8y + 7 >= 3 = if#(y,false(),true()) =#(x,y) = x + 8y + 7 >= 4y + 4 = if#(x,y,if(y,false(),true())) not(x) = 4x + 5 >= 3x + 3 = if(x,false(),true()) and(x,y) = 4x + 8y + 3 >= 3x + 1y + 2 = if(x,y,false()) or(x,y) = 4x + 2y + 4 >= 3x + 1y + 3 = if(x,true(),y) implies(x,y) = 4x + 2y + 4 >= 3x + 1y + 3 = if(x,y,true()) =(x,x) = 13x + 7 >= 2 = true() =(x,y) = 4x + 13y + 7 >= 3x + 5y + 6 = if(x,y,not(y)) if(true(),x,y) = 1x + 1y + 5 >= x = x if(false(),x,y) = 1x + 1y + 3 >= y = y if(x,x,if(x,false(),true())) = 4x + 4 >= 2 = true() =(x,y) = 4x + 13y + 7 >= 3x + 4y + 4 = if(x,y,if(y,false(),true())) problem: DPs: TRS: not(x) -> if(x,false(),true()) and(x,y) -> if(x,y,false()) or(x,y) -> if(x,true(),y) implies(x,y) -> if(x,y,true()) =(x,x) -> true() =(x,y) -> if(x,y,not(y)) if(true(),x,y) -> x if(false(),x,y) -> y if(x,x,if(x,false(),true())) -> true() =(x,y) -> if(x,y,if(y,false(),true())) Qed