[M, N] -> { S1[i0, i1, i2] -> [0, i0, 0, i1 + i2, 0, i2, 0] : i0 >= 1 and i0 <= M and i1 <= N and i2 >= 1 and i2 <= -1 + i1; S2[i0, i1] -> [0, i0, 0, -1 + 2i1, 1, 0, 0] : i0 >= 1 and i0 <= M and i1 >= 1 and i1 <= N }
[M, N] -> {  :  }
[M, N] -> { [i, j, k, l, m, n, o] -> separate[o0] }