Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline

H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
maze = [input() for _ in range(H)]
warp_cnts = [[None]*(W) for j in range(H)]

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])
        

mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  while len(mv_a_tgs):
    tg0,tg1 = mv_a_tgs.pop()
    mv_a(tg0,tg1)
  while len(mv_b_tgs):
    wp0,wp1 = mv_b_tgs.pop()
    mv_b(wp0,wp1)
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline

H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = []
for h in range(-2,3,1):
  for w in range(-2,3,1):
    if h != 0 or w != 0:
      mv_b_pts.append([h,w])
maze = [input() for _ in range(H)]
warp_cnts = [[None]*(W) for j in range(H)]

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])
        

mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  while len(mv_a_tgs):
    tg0,tg1 = mv_a_tgs.pop()
    mv_a(tg0,tg1)
  while len(mv_b_tgs):
    wp0,wp1 = mv_b_tgs.pop()
    mv_b(wp0,wp1)
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline

H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = []
for h in range(-2,3,1):
  for w in range(-2,3,1):
    if h != 0 or w != 0:
      mv_b_pts.append([h,w])
maze = [input() for _ in range(H)]
warp_cnts = [[None]*(W) for j in range(H)]

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])
        

mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  while len(mv_a_tgs):
    tg0,tg1 = mv_a_tgs.pop()
    mv_a(tg0,tg1)
  while len(mv_b_tgs):
    wp0,wp1 = mv_b_tgs.pop()
    mv_b(wp0,wp1)
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline

H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = []
for h in range(-2,3,1):
  for w in range(-2,3,1):
    if h != 0 or w != 0:
      mv_b_pts.append([h,w])
maze = [input() for _ in range(H)]
warp_cnts = [[None]*(W) for j in range(H)]

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])
        

mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  while len(mv_a_tgs):
    tg = mv_a_tgs.pop()
    mv_a(tg[0],tg[1])
  while len(mv_b_tgs):
    wp = mv_b_tgs.pop()
    mv_b(wp[0],wp[1])
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline

H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = []
for h in range(-2,3,1):
  for w in range(-2,3,1):
    if h != 0 or w != 0:
      mv_b_pts.append([h,w])
maze = [input() for _ in range(H)]
warp_cnts = [[None]*(W) for j in range(H)]

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])
        

mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  while len(mv_a_tgs):
    tg = mv_a_tgs.pop()
    mv_a(tg[0],tg[1])
  while len(mv_b_tgs):
    wp = mv_b_tgs.pop()
    mv_b(wp[0],wp[1])
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Time Limit Exceeded):
H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = []
for h in range(-2,3,1):
  for w in range(-2,3,1):
    if h != 0 or w != 0:
      mv_b_pts.append([h,w])
maze = []
warp_cnts = [[None]*(W) for j in range(H)]
for i in range(H):
  maze.append(input())

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])


mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  while len(mv_a_tgs):
    tg = mv_a_tgs.pop()
    mv_a(tg[0],tg[1])
  while len(mv_b_tgs):
    wp = mv_b_tgs.pop()
    mv_b(wp[0],wp[1])
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Time Limit Exceeded):
H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = []
for h in range(-2,3,1):
  for w in range(-2,3,1):
    if h != 0 or w != 0:
      mv_b_pts.append([h,w])
maze = []
warp_cnts = [[None]*(W) for j in range(H)]
for i in range(H):
  maze.append(input())

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)
        

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])
        

mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  mv_b_tgs=[]
  for tg in mv_a_tgs:
    mv_a(tg[0],tg[1])
  mv_a_tgs = []
  for wp in mv_b_tgs:
    mv_b(wp[0],wp[1])
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Time Limit Exceeded):
H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv_a_pts = [[-1,0],[1,0],[0,-1],[0,1]]
mv_b_pts = []
for h in range(-2,3,1):
  for w in range(-2,3,1):
    if h != 0 or w != 0:
      mv_b_pts.append([h,w])
maze = []
warp_cnts = [[None]*(W) for j in range(H)]
for i in range(H):
  maze.append(input())

def mv_a(h,w):
  mv_b_tgs.append([h,w])
  warp_cnts[h][w] = cnt
  for vh,vw in mv_a_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a(tgh,tgw)
        

def mv_b(h,w):
  for vh,vw in mv_b_pts:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if warp_cnts[tgh][tgw] is None and maze[tgh][tgw] != "#":
        mv_a_tgs.append([tgh,tgw])
        

mv_b_tgs=[]
mv_a_tgs = [[sh-1,sw-1]]
cnt = 0
while len(mv_a_tgs)>0:
  mv_b_tgs=[]
  for tg in mv_a_tgs:
    mv_a(tg[0],tg[1])
  mv_a_tgs = []
  for wp in mv_b_tgs:
    mv_b(wp[0],wp[1])
  cnt+=1
print(-1 if warp_cnts[eh-1][ew-1] is None else warp_cnts[eh-1][ew-1])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])

Buggy python submission (verdict: Runtime Error):
H,W = map(int , input().split())
sh,sw = map(int , input().split())
eh,ew = map(int , input().split())
mv = [[-1,0],[1,0],[0,-1],[0,1]]
warplist = []
for h in range(-2,2,1):
  for w in range(-2,2,1):
    if h!=0 and w!=0:
      warplist.append([h,w])
maze = []
goned = [[None]*(W) for j in range(H)]
for i in range(H):
  maze.append(input())

def wfs(h,w):
  goned[h][w] = cnt
  for vh,vw in mv:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if goned[tgh][tgw] is None and maze[tgh][tgw] != "#":
        wfs(tgh,tgw)
        wps.append([tgh,tgw])

def warp(h,w):
  for vh,vw in warplist:
    tgh = h + vh
    tgw = w + vw
    if 0 <= tgh <= H-1 and 0 <= tgw <= W-1 :
      if goned[tgh][tgw] is None and maze[tgh][tgw] != "#":
        tgs.append([tgh,tgw])
wps=[]
tgs = [[sh-1,sw-1]]
cnt = 0
while len(tgs)>0:
  wps=[]
  for tg in tgs:
    wfs(tg[0],tg[1])
  tgs = []
  for wp in wps:
    warp(wp[0],wp[1])
  cnt+=1
print(-1 if goned[eh][ew] is None else goned[eh][ew])

Fixed submission:
from collections import deque
 
 
walk = [(1, 0), (-1, 0), (0, 1), (0, -1)]
warp = [(-2, -2), (-2, -1), (-2, 0), (-2, 1), (-2, 2),
        (-1, -2), (-1, -1), (-1, 0), (-1, 1), (-1, 2),
        (0, -2), (0, -1), (0, 1), (0, 2),
        (1, -2), (1, -1), (1, 0), (1, 1), (1, 2),
        (2, -2), (2, -1), (2, 0), (2, 1), (2, 2),]
 
 
def get_warped(walked, map_):
    warped = deque()
    while walked:
        h, w = walked.popleft()
        for i, j in warp:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                warped.append((h2, w2))
                map_[h2][w2] = map_[h][w] + 1
    return warped, map_
 
 
def get_walked(candidate, map_):
    walked = deque()
    while candidate:
        h, w = candidate.popleft()
        walked.append((h, w))
        for i, j in walk:
            h2 = h + i
            w2 = w + j
            if -1 < h2 < H and -1 < w2 < W and map_[h2][w2] == '.':
                candidate.append((h2, w2))
                map_[h2][w2] = map_[h][w]
    return walked, map_
 
H, W = map(int, input().split())
s_h, s_w = [i-1 for i in map(int, input().split())]
d_h, d_w = [i-1 for i in map(int, input().split())]
map_ = [list(input()) for i in range(H)]
 
candidate = deque([(s_h, s_w)])
map_[s_h][s_w] = 0
 
while candidate:
    walked, map_ = get_walked(candidate, map_)
    candidate, map_ = get_warped(walked, map_)
 
for h in range(H):
    for w in range(W):
        if map_[h][w] == '.':
            map_[h][w] = -1
 
print(map_[d_h][d_w])