[a, b] -> { s2[i] -> [i, 2] : i >= 20 + a and i <= 20 + b; s0[i] -> [i, 0] : i >= a and i <= b; s1[i] -> [i, 1] : i >= 10 + a and i <= 10 + b }
{  :  }
[a, b] -> { [i0, i1] -> atomic[o0] : o0 <= -1; [i0, i1] -> separate[o0] : o0 >= 0 }