YES(?,O(n^2)) Problem: *(i(x),x) -> 1() *(1(),y) -> y *(x,0()) -> 0() *(*(x,y),z) -> *(x,*(y,z)) Proof: RT Transformation Processor: strict: *(i(x),x) -> 1() *(1(),y) -> y *(x,0()) -> 0() *(*(x,y),z) -> *(x,*(y,z)) weak: Matrix Interpretation Processor: dimension: 1 interpretation: [0] = 29, [1] = 0, [*](x0, x1) = x0 + x1, [i](x0) = x0 + 16 orientation: *(i(x),x) = 2x + 16 >= 0 = 1() *(1(),y) = y >= y = y *(x,0()) = x + 29 >= 29 = 0() *(*(x,y),z) = x + y + z >= x + y + z = *(x,*(y,z)) problem: strict: *(1(),y) -> y *(x,0()) -> 0() *(*(x,y),z) -> *(x,*(y,z)) weak: *(i(x),x) -> 1() Matrix Interpretation Processor: dimension: 1 interpretation: [0] = 1, [1] = 4, [*](x0, x1) = x0 + x1 + 4, [i](x0) = x0 orientation: *(1(),y) = y + 8 >= y = y *(x,0()) = x + 5 >= 1 = 0() *(*(x,y),z) = x + y + z + 8 >= x + y + z + 8 = *(x,*(y,z)) *(i(x),x) = 2x + 4 >= 4 = 1() problem: strict: *(*(x,y),z) -> *(x,*(y,z)) weak: *(1(),y) -> y *(x,0()) -> 0() *(i(x),x) -> 1() Matrix Interpretation Processor: dimension: 2 interpretation: [0] [0] = [2], [0] [1] = [6], [1 4] [0] [*](x0, x1) = [0 1]x0 + x1 + [4], [1 0] [0] [i](x0) = [0 0]x0 + [2] orientation: [1 8] [1 4] [16] [1 4] [1 4] [0] *(*(x,y),z) = [0 1]x + [0 1]y + z + [8 ] >= [0 1]x + [0 1]y + z + [8] = *(x,*(y,z)) [24] *(1(),y) = y + [10] >= y = y [1 4] [0] [0] *(x,0()) = [0 1]x + [6] >= [2] = 0() [2 0] [8] [0] *(i(x),x) = [0 1]x + [6] >= [6] = 1() problem: strict: weak: *(*(x,y),z) -> *(x,*(y,z)) *(1(),y) -> y *(x,0()) -> 0() *(i(x),x) -> 1() Qed