The system is accessible function passing by a sort ordering that equates all sorts.

We start by computing the following initial DP problem:

  P1. (1) random#(x) => rand#(x, 0)
      (2) rand#(x, y) => id_inc#(y) | x > 0
      (3) rand#(x, y) => rand#(-x + 1, id_inc(y)) | x > 0
      (4) rand#(x, y) => id_dec#(y) | 0 > x
      (5) rand#(x, y) => rand#(-x - 1, id_dec(y)) | 0 > x

***** We apply the Graph Processor on P1.

There is only one SCC, so all DPs not inside the SCC can be removed:

  P2. (1) rand#(x, y) => rand#(-x + 1, id_inc(y)) | x > 0
      (2) rand#(x, y) => rand#(-x - 1, id_dec(y)) | 0 > x

***** No progress could be made on DP problem P2.