Advent of code 2022 day 20

# Using numba with doubly-linked list approach adapted from
# https://github.com/shaeberling/euler/blob/master/kotlin/src/com/s13g/aoc/aoc2022/Day20.kt

@numba.njit
def day20_mix(a):
  for i in range(len(a)):  # pylint: disable=consider-using-enumerate
    value, prev_, next_ = a[i]
    offset = value % (len(a) - 1)
    if offset != 0:
      a[next_, 1], a[prev_, 2] = prev_, next_  # Disconnect node i.
      prev_ = i
      if offset < len(a) // 2:
        for _ in range(offset):
          prev_ = a[prev_, 2]
      else:
        for _ in range(len(a) - offset):
          prev_ = a[prev_, 1]
      next_ = a[prev_, 2]
      a[i, 1], a[i, 2], a[prev_, 2], a[next_, 1] = prev_, next_, i, i  # Reconnect node i.


def day20(s, *, part2=False):
  a = np.array(list(map(int, s.splitlines())))
  a *= 811_589_153 if part2 else 1
  a = np.array([[value, (i - 1) % len(a), (i + 1) % len(a)] for i, value in enumerate(a)])
  for _ in range(10 if part2 else 1):
    day20_mix(a)

  (i,), = np.nonzero(a[:, 0] == 0)
  values = []
  for _ in range(len(a)):
    values.append(a[i, 0])
    i = a[i, 2]
  return sum(values[offset % len(a)] for offset in [1000, 2000, 3000])