Buggy python submission (verdict: Time Limit Exceeded):
import sys
from collections import deque
h,w = map(int,input().split())
sx,sy = map(int,input().split())
sx -= 1
sy -= 1
gx,gy = map(int,input().split())
gx -= 1
gy -= 1
route = []
for i in range(h):
  lst = list(input())
  route.append(lst)
  
brock = [['#']*w for i in range(h)]
s = 0
que = deque([])
dx = [-1,0,1,0]
dy = [0,-1,0,1]

brock[sx][sy] = 0
que.append((sx,sy))



while que:
  
  (p,q) = que.popleft()
  if (p,q) == (gx,gy):
    print(brock[gx][gy])
    sys.exit()
  for i in range(4):
    p2,q2 = p+dx[i],q+dy[i]
    if 0 <= p2 < h and 0<= q2 < w and route[p2][q2] == '.' and brock[p2][q2] == '#':
      brock[p2][q2] = brock[p][q]
      que.append((p2,q2))
      
  
  if len(que) == 0:
    
    s += 1
    for u in range(h):
      for v in range(w):
        if brock[u][v] == s-1:
          x,y = u,v
          for j in range(-2,3):
             for k in range(-2,3):
                x2 = x+j
                y2 = y+k
                if 0 <= x2 < h and 0<= y2 < w and route[x2][y2] == '.' and brock[x2][y2] == '#':
                  brock[x2][y2] = s
                  que.append((x2,y2))
            
                  
              
print(-1)              
            



Fixed submission:
import sys
from collections import deque
h,w = map(int,input().split())
sx,sy = map(int,input().split())
sx -= 1
sy -= 1
gx,gy = map(int,input().split())
gx -= 1
gy -= 1
route = []
for i in range(h):
  lst = list(input())
  route.append(lst)
  
brock = [['#']*w for i in range(h)]

que = deque([])
dx = [-1,0,1,0]
dy = [0,-1,0,1]

brock[sx][sy] = 0
que.append((sx,sy))



while que:
  
  (p,q) = que.popleft()
  if (p,q) == (gx,gy):
    print(brock[gx][gy])
    sys.exit()
  for i in range(4):
    p2,q2 = p+dx[i],q+dy[i]
    if 0 <= p2 < h and 0<= q2 < w and route[p2][q2] == '.' and (brock[p2][q2] == '#' or brock[p2][q2] > brock[p][q]):
      brock[p2][q2] = brock[p][q]
      que.appendleft((p2,q2))
  
  for j in range(-2,3):
    for k in range(-2,3):
      p3 = p+j
      q3 = q+k
      if 0 <= p3 < h and 0<= q3 < w and route[p3][q3] == '.' and brock[p3][q3] == '#':
        brock[p3][q3] = brock[p][q]+1
        que.append((p3,q3))
        
        
            
                  
              
print(-1)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from collections import deque
h,w = map(int,input().split())
sx,sy = map(int,input().split())
sx -= 1
sy -= 1
gx,gy = map(int,input().split())
gx -= 1
gy -= 1
route = []
for i in range(h):
  lst = list(input())
  route.append(lst)
  
brock = [['#']*w for i in range(h)]
s = 0
que = deque([])
dx = [-1,0,1,0]
dy = [0,-1,0,1]

brock[sx][sy] = 0
que.append((sx,sy))
lst = [(sx,sy)]


while que:
  
  (p,q) = que.popleft()
  if (p,q) == (gx,gy):
    print(brock[gx][gy])
    sys.exit()
  for i in range(4):
    p2,q2 = p+dx[i],q+dy[i]
    if 0 <= p2 < h and 0<= q2 < w and route[p2][q2] == '.' and brock[p2][q2] == '#':
      brock[p2][q2] = brock[p][q]
      que.append((p2,q2))
      lst.append((p2,q2))
  
  if len(que) == 0:
    
    s += 1
    for u in range(h):
      for v in range(w):
        if brock[u][v] == s-1:
          x,y = u,v
          for j in range(-2,3):
             for k in range(-2,3):
                x2 = x+j
                y2 = y+k
                if 0 <= x2 < h and 0<= y2 < w and route[x2][y2] == '.' and brock[x2][y2] == '#':
                  brock[x2][y2] = s
                  que.append((x2,y2))
            
                  
              
print(-1)              
            



Fixed submission:
import sys
from collections import deque
h,w = map(int,input().split())
sx,sy = map(int,input().split())
sx -= 1
sy -= 1
gx,gy = map(int,input().split())
gx -= 1
gy -= 1
route = []
for i in range(h):
  lst = list(input())
  route.append(lst)
  
brock = [['#']*w for i in range(h)]

que = deque([])
dx = [-1,0,1,0]
dy = [0,-1,0,1]

brock[sx][sy] = 0
que.append((sx,sy))



while que:
  
  (p,q) = que.popleft()
  if (p,q) == (gx,gy):
    print(brock[gx][gy])
    sys.exit()
  for i in range(4):
    p2,q2 = p+dx[i],q+dy[i]
    if 0 <= p2 < h and 0<= q2 < w and route[p2][q2] == '.' and (brock[p2][q2] == '#' or brock[p2][q2] > brock[p][q]):
      brock[p2][q2] = brock[p][q]
      que.appendleft((p2,q2))
  
  for j in range(-2,3):
    for k in range(-2,3):
      p3 = p+j
      q3 = q+k
      if 0 <= p3 < h and 0<= q3 < w and route[p3][q3] == '.' and brock[p3][q3] == '#':
        brock[p3][q3] = brock[p][q]+1
        que.append((p3,q3))
        
        
            
                  
              
print(-1)

Buggy python submission (verdict: Runtime Error):
h,w = map(int,input().split())
sx,sy = map(int,input().split())
sx -= 1
sy -= 1
gx,gy = map(int,input().split())
gx -= 1
gy -= 1
route = []
for i in range(h):
  lst = list(input())
  route.append(lst)
  
brock = [['#']*w for i in range(h)]
s = 0
que = deque([])
dx = [-1,0,1,0]
dy = [0,-1,0,1]

brock[sx][sy] = 0
que.append((sx,sy))
lst = [(sx,sy)]


while que:
  
  (p,q) = que.popleft()
  if (p,q) == (gx,gy):
    print(brock[gx][gy])
    sys.exit()
  for i in range(4):
    p2,q2 = p+dx[i],q+dy[i]
    if 0 <= p2 < h and 0<= q2 < w and route[p2][q2] == '.' and brock[p2][q2] == '#':
      brock[p2][q2] = brock[p][q]
      que.append((p2,q2))
      lst.append((p2,q2))
  
  if len(que) == 0:
    
    s += 1
    for u in range(h):
      for v in range(w):
        if brock[u][v] == s-1:
          x,y = u,v
          for j in range(-2,3):
             for k in range(-2,3):
                x2 = x+j
                y2 = y+k
                if 0 <= x2 < h and 0<= y2 < w and route[x2][y2] == '.' and brock[x2][y2] == '#':
                  brock[x2][y2] = s
                  que.append((x2,y2))
            
                  
              
print(-1)              
            



Fixed submission:
import sys
from collections import deque
h,w = map(int,input().split())
sx,sy = map(int,input().split())
sx -= 1
sy -= 1
gx,gy = map(int,input().split())
gx -= 1
gy -= 1
route = []
for i in range(h):
  lst = list(input())
  route.append(lst)
  
brock = [['#']*w for i in range(h)]

que = deque([])
dx = [-1,0,1,0]
dy = [0,-1,0,1]

brock[sx][sy] = 0
que.append((sx,sy))



while que:
  
  (p,q) = que.popleft()
  if (p,q) == (gx,gy):
    print(brock[gx][gy])
    sys.exit()
  for i in range(4):
    p2,q2 = p+dx[i],q+dy[i]
    if 0 <= p2 < h and 0<= q2 < w and route[p2][q2] == '.' and (brock[p2][q2] == '#' or brock[p2][q2] > brock[p][q]):
      brock[p2][q2] = brock[p][q]
      que.appendleft((p2,q2))
  
  for j in range(-2,3):
    for k in range(-2,3):
      p3 = p+j
      q3 = q+k
      if 0 <= p3 < h and 0<= q3 < w and route[p3][q3] == '.' and brock[p3][q3] == '#':
        brock[p3][q3] = brock[p][q]+1
        que.append((p3,q3))
        
        
            
                  
              
print(-1)