Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque

h, w = map(int, input().split())
ch, cw = map(lambda x: int(x)-1, input().split())
dh, dw = map(lambda x: int(x)-1, input().split())
maze = [input() for _ in range(h)]

INF = 10**12
path = [[INF] * w for _ in range(h)] #ここに各マスの移動コストを記録する

walk = [(1,0), (0,1), (-1,0), (0,-1)] #ワープしない移動
warp = [(i,j) for i in range(-2,3) for j in range(-2,3) if (i,j) not in [(0,0)] + walk] #ワープするときの移動

q = deque()
path[ch][cw] = 0
q.append((ch, cw, 0))

while q:
    x, y, s = q.popleft()
    for dx, dy in walk:
        nx = x + dx
        ny = y + dy
        if 0 <= nx < h and 0 <= ny < w and maze[nx][ny] != "#" and path[nx][ny] > s:
            path[nx][ny] = s
            q.append((nx, ny, s))
    for dx, dy in warp:
        nx = x + dx
        ny = y + dy
        if 0 <= nx < h and 0 <= ny < w and maze[nx][ny] != "#" and path[nx][ny] > s+1:
            path[nx][ny] = s+1
            q.append((nx, ny, s+1))

ans = path[dh][dw] if path[dh][dw] < INF else -1
print(ans)

Fixed submission:
from collections import deque


H, W = map(int, input().split())
Ch, Cw = map(lambda x: int(x) - 1, input().split())
Dh, Dw = map(lambda x: int(x) - 1, input().split())
maze = [input() for _ in range(H)]

INF = 10 ** 12
path = [[INF] * W for _ in range(H)]  # path: 各マスへの移動コスト

# walk:移動A, warp:移動B
walk = [(0, 1), (0, -1), (-1, 0), (1, 0)]
warp = [(i, j) for i in range(-2, 3) for j in range(-2, 3) if (i, j) not in [(0, 0)] + walk]

q = deque()
path[Ch][Cw] = 0
q.append((Ch, Cw, 0))

while q:
    x, y, s = q.popleft()
    for dx, dy in walk:  # 移動A
        nx = x + dx
        ny = y + dy
        if 0 <= nx < H and 0 <= ny < W and maze[nx][ny] == '.' and path[nx][ny] > s:
            path[nx][ny] = s
            q.appendleft((nx, ny, s))  # 移動Aの場合はコスト0. キューの先頭に追加する.
    for dx, dy in warp:  # 移動B
        nx = x + dx
        ny = y + dy
        if 0 <= nx < H and 0 <= ny < W and maze[nx][ny] == '.' and path[nx][ny] > s + 1:
            path[nx][ny] = s + 1
            q.append((nx, ny, s + 1))  # 移動Bの場合はコスト1. キューの最後尾に追加する.
    
ans = path[Dh][Dw] if path[Dh][Dw] < INF else '-1'
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque

h, w = map(int, input().split())
ch, cw = map(lambda x: int(x)-1, input().split())
dh, dw = map(lambda x: int(x)-1, input().split())
maze = [input() for _ in range(h)]

INF = float('inf')
path = [[INF] * w for _ in range(h)] #ここに各マスの移動コストを記録する

walk = [(1,0), (0,1), (-1,0), (0,-1)] #ワープしない移動
warp = [(i,j) for i in range(-2,3) for j in range(-2,3) if (i,j) not in [(0,0)] + walk] #ワープするときの移動

q = deque()
path[ch][cw] = 0
q.append((ch, cw, 0))

while q:
    x, y, s = q.popleft()
    for dx, dy in walk:
        nx = x + dx
        ny = y + dy
        if 0 <= nx < h and 0 <= ny < w and maze[nx][ny] != "#" and path[nx][ny] > s:
            path[nx][ny] = s
            q.append((nx, ny, s))
    for dx, dy in warp:
        nx = x + dx
        ny = y + dy
        if 0 <= nx < h and 0 <= ny < w and maze[nx][ny] != "#" and path[nx][ny] > s+1:
            path[nx][ny] = s+1
            q.append((nx, ny, s+1))

ans = path[dh][dw] if path[dh][dw] < INF else -1
print(ans)

Fixed submission:
from collections import deque


H, W = map(int, input().split())
Ch, Cw = map(lambda x: int(x) - 1, input().split())
Dh, Dw = map(lambda x: int(x) - 1, input().split())
maze = [input() for _ in range(H)]

INF = 10 ** 12
path = [[INF] * W for _ in range(H)]  # path: 各マスへの移動コスト

# walk:移動A, warp:移動B
walk = [(0, 1), (0, -1), (-1, 0), (1, 0)]
warp = [(i, j) for i in range(-2, 3) for j in range(-2, 3) if (i, j) not in [(0, 0)] + walk]

q = deque()
path[Ch][Cw] = 0
q.append((Ch, Cw, 0))

while q:
    x, y, s = q.popleft()
    for dx, dy in walk:  # 移動A
        nx = x + dx
        ny = y + dy
        if 0 <= nx < H and 0 <= ny < W and maze[nx][ny] == '.' and path[nx][ny] > s:
            path[nx][ny] = s
            q.appendleft((nx, ny, s))  # 移動Aの場合はコスト0. キューの先頭に追加する.
    for dx, dy in warp:  # 移動B
        nx = x + dx
        ny = y + dy
        if 0 <= nx < H and 0 <= ny < W and maze[nx][ny] == '.' and path[nx][ny] > s + 1:
            path[nx][ny] = s + 1
            q.append((nx, ny, s + 1))  # 移動Bの場合はコスト1. キューの最後尾に追加する.
    
ans = path[Dh][Dw] if path[Dh][Dw] < INF else '-1'
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque

h, w = map(int, input().split())
ch, cw = map(lambda x: int(x)-1, input().split())
dh, dw = map(lambda x: int(x)-1, input().split())
maze = [input() for _ in range(h)]

INF = float('inf')
path = [[INF] * w for _ in range(h)] #ここに各マスの移動コストを記録する

walk = [(1,0), (0,1), (-1,0), (0,-1)] #ワープしない移動
warp = [(i,j) for i in range(-2,3) for j in range(-2,3) if (i,j) not in [(0,0)] + walk] #ワープするときの移動

q = deque()
path[ch][cw] = 0
q.append((ch, cw, 0))

while q:
    x, y, s = q.popleft()
    for dx, dy in walk:
        nx = x + dx
        ny = y + dy
        if 0 <= nx < h and 0 <= ny < w and maze[nx][ny] != "#" and path[nx][ny] > s:
            path[nx][ny] = s
            q.append((nx, ny, s))
    for dx, dy in warp:
        nx = x + dx
        ny = y + dy
        if 0 <= nx < h and 0 <= ny < w and maze[nx][ny] != "#" and path[nx][ny] > s+1:
            path[nx][ny] = s+1
            q.append((nx, ny, s+1))

ans = path[dh][dw] if path[dh][dw] < INF else -1
print(ans)

Fixed submission:
from collections import deque


H, W = map(int, input().split())
Ch, Cw = map(lambda x: int(x) - 1, input().split())
Dh, Dw = map(lambda x: int(x) - 1, input().split())
maze = [input() for _ in range(H)]

INF = 10 ** 12
path = [[INF] * W for _ in range(H)]  # path: 各マスへの移動コスト

# walk:移動A, warp:移動B
walk = [(0, 1), (0, -1), (-1, 0), (1, 0)]
warp = [(i, j) for i in range(-2, 3) for j in range(-2, 3) if (i, j) not in [(0, 0)] + walk]

q = deque()
path[Ch][Cw] = 0
q.append((Ch, Cw, 0))

while q:
    x, y, s = q.popleft()
    for dx, dy in walk:  # 移動A
        nx = x + dx
        ny = y + dy
        if 0 <= nx < H and 0 <= ny < W and maze[nx][ny] == '.' and path[nx][ny] > s:
            path[nx][ny] = s
            q.appendleft((nx, ny, s))  # 移動Aの場合はコスト0. キューの先頭に追加する.
    for dx, dy in warp:  # 移動B
        nx = x + dx
        ny = y + dy
        if 0 <= nx < H and 0 <= ny < W and maze[nx][ny] == '.' and path[nx][ny] > s + 1:
            path[nx][ny] = s + 1
            q.append((nx, ny, s + 1))  # 移動Bの場合はコスト1. キューの最後尾に追加する.
    
ans = path[Dh][Dw] if path[Dh][Dw] < INF else '-1'
print(ans)