from collections import deque
from lib import get_data
from lib import Grid2D


data = """###############
#...#...#.....#
#.#.#.#.#.###.#
#S#...#.#.#...#
#######.#.#.###
#######.#.#...#
#######.#.###.#
###..E#...#...#
###.#######.###
#...###...#...#
#.#####.#.###.#
#.#...#.#.#...#
#.#.#.#.#.#.###
#...#...#...###
###############
"""
data = get_data(__file__)

g = Grid2D(data)

(start,) = g.find("S")
(end,) = g.find("E")

cost = 0
sd = dict()
de = dict()

queue = deque([(start[0], start[1], 0)])
seen = set()
while queue:
    r, c, cost = queue.popleft()

    if (r, c) in sd:
        continue
    sd[(r, c)] = cost

    if (r, c) == end:
        break

    for r, c in g.neighbors_ort((r, c)):
        if g[(r, c)] != "#":
            queue.append((r, c, cost + 1))

seen = set()
queue = deque([(end[0], end[1], 0)])
while queue:
    r, c, cost = queue.popleft()

    if (r, c) in de:
        continue
    de[(r, c)] = cost

    if (r, c) == start:
        break

    for r, c in g.neighbors_ort((r, c)):
        if g[(r, c)] != "#":
            queue.append((r, c, cost + 1))

for max_steps in [2, 20]:
    cheats = set()
    for cr, cc in g.find("S."):
        start = cr, cc, 0
        seen = set()
        queue = deque([start])
        while queue:
            r, c, steps = queue.popleft()
            if steps > max_steps:
                continue

            if (r, c) in seen:
                continue
            seen.add((r, c))

            if g[(r, c)] != "#":
                ncost = sd[(cr, cc)] + steps + de[(r, c)]
                if cost - ncost >= 100:
                    cheats.add((cr, cc, r, c))

            for dr, dc in [(-1, 0), (0, 1), (1, 0), (0, -1)]:
                nr, nc = r + dr, c + dc
                if g.contains((nr, nc)):
                    queue.append((nr, nc, steps + 1))

    print(len(cheats))