(n, interval=1)
| 34 | random.seed(42) |
| 35 | |
| 36 | def forward_backward_permutations(n, interval=1): |
| 37 | original = list(range(n)) |
| 38 | result = [original] |
| 39 | for i in range(1, n): |
| 40 | new_list = original[i::interval] |
| 41 | result.append(new_list) |
| 42 | new_list = original[: i + 1][::-interval] |
| 43 | result.append(new_list) |
| 44 | return result |
| 45 | |
| 46 | def listify(elems): |
| 47 | return [x for e in elems for x in e] |