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) map#(Z, cons(U, V)) => map#(Z, V)
      (2) flatten#(node(W, P)) => flatten#(X{12})
      (3) flatten#(node(W, P)) => map#(flatten, P)
      (4) flatten#(node(W, P)) => concat#(map(flatten, P))
      (5) concat#(cons(X1, Y1)) => concat#(Y1)
      (6) concat#(cons(X1, Y1)) => append#(X1, concat(Y1))
      (7) append#(cons(V1, W1), P1) => append#(W1, P1)

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

Considering the 4 SCCs, this DP problem is split into the following new problems.

  P2. (1) map#(Z, cons(U, V)) => map#(Z, V)

  P3. (1) append#(cons(V1, W1), P1) => append#(W1, P1)

  P4. (1) concat#(cons(X1, Y1)) => concat#(Y1)

  P5. (1) flatten#(node(W, P)) => flatten#(X{12})

***** We apply the Subterm Criterion Processor on P2.

We use the following projection function:

  nu(map#) = 2

We thus have:

  (1) cons(U, V) |>| V

All DPs are strictly oriented, and may be removed.  Hence, this DP problem is finite.

***** We apply the Subterm Criterion Processor on P3.

We use the following projection function:

  nu(append#) = 1

We thus have:

  (1) cons(V1, W1) |>| W1

All DPs are strictly oriented, and may be removed.  Hence, this DP problem is finite.

***** We apply the Subterm Criterion Processor on P4.

We use the following projection function:

  nu(concat#) = 1

We thus have:

  (1) cons(X1, Y1) |>| Y1

All DPs are strictly oriented, and may be removed.  Hence, this DP problem is finite.

***** No progress could be made on DP problem P5.