| H[r1].nxt = H[ce.nxt].nxt, path(r ' + x, H), reachable(r, r1, H), ce.nxt ∈ H ⊦ ce.nxt = null, reachable(r, ce.nxt, H), reachable(r, (r ' + x).last, H[r1, ce]) |
H[r1].nxt = H[ce.nxt].nxt, path(r ' + (r0 + x0), H), reachable(r, r1, H), ce.nxt ∈ H, ∀ H, r1, ce, r. H[r1].nxt = H[ce.nxt].nxt ∧ path(r ' + x0, H) ∧ reachable(r, r1, H) ∧ ce.nxt ∈ H → ce.nxt = null ∨ reachable(r, ce.nxt, H) ∨ reachable(r, (r ' + x0).last, H[r1, ce]) ⊦ ce.nxt = null, reachable(r, (r ' + (r0 + x0)).last, H[r1, ce]), reachable(r, ce.nxt, H)
Used simplifier rules: path-one: ⊦ path(r ', H) ↔ r ∈ H ∧ r ≠ null;%self-reachable: ⊦ reachable(r, r, H) ↔ r ≠ null ∧ r ∈ H;%reflist freely generated by [], +;;% ⊦ x0 + [] = x0; (s)%a: ⊦ (x0 + x1) + x2 = x0 + x1 + x2; from specification list[reflist]% ⊦ r '.last = r; (s)% ⊦ r ∈ H[r0, ce] ↔ r = r0 ∨ r ∈ H; (ws)