Advent of code 2023 day 12 fast

def day12(s0, *, part2=False):  # Dynamic programming, without numba.
  total = 0

  for line in s0.splitlines():
    s, right = line.split()
    counts = tuple(map(int, right.split(',')))
    if part2:
      s = '?'.join([s] * 5)
      counts *= 5

    s += '.'
    # Dynamic programming over the string position and the counts position.
    num_matches = np.zeros((len(s) + 1, len(counts) + 1), int)
    num_matches[0, 0] = 1

    for s_index in range(len(s)):
      for counts_index in range(len(counts) + 1):
        if num := num_matches[s_index, counts_index]:
          if s[s_index] != '#':
            num_matches[s_index + 1, counts_index] += num
          if counts_index < len(counts):
            n = counts[counts_index]
            if s[s_index : s_index + n].replace('?', '#') == '#' * n and s[s_index + n] != '#':
              num_matches[s_index + n + 1, counts_index + 1] += num

    total += num_matches[-1, -1]

  return total