Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
ch,cw = map(int,input().split())
dh,dw = map(int,input().split())
S = 2*[(W+4)*"#"]+["##"+input()+"##" for h in range(H)]+2*[(W+4)*"#"]
ans = [(W+4)*[-1] for h in range(H+4)]
ans[ch+1][cw+1] = 0
move = [[-1,0],[1,0],[0,-1],[0,1]]
magic = [[-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],[-1,-2],[-1,-1],[-1,1],[-1,2],[0,-2],[0,2],[1,-2],[1,-1],[1,1],[1,2],[2,-2],[2,-1],[2,0],[2,1],[2,2]]

for h in range(H+4):
  for w in range(W+4):
    if S[h][w]=="#":
      ans[h][w]=-2

P = deque([[ch+1,cw+1]])
Q = deque([])

while P:
  x1,y1 = P.popleft()
  Q.append([x1,y1])
  for dx,dy in move:
    x = x1+dx
    y = y1+dy
    if ans[x][y]==-1:
      ans[x][y] = ans[x1][y1]
      P.append([x,y])
  
  if len(P)==0:
    while Q:
      x2,y2 = Q.popleft()
      for dx,dy in magic:
        x = x2+dx
        y = y2+dy
        if ans[x][y]==-1:
          ans[x][y] = ans[x2][y2]+1
          P.append([x,y])

print(ans[dh+1][dw+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
ch,cw = map(int,input().split())
dh,dw = map(int,input().split())
S = 2*[(W+4)*"#"]+["##"+input()+"##" for h in range(H)]+2*[(W+4)*"#"]
ans = [(W+4)*[-1] for h in range(H+4)]
ans[ch+1][cw+1] = 0
move = [[-1,0],[1,0],[0,-1],[0,1]]
magic = [[-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],[-1,-2],[-1,-1],[-1,1],[-1,2],[0,-2],[0,2],[1,-2],[1,-1],[1,1],[1,2],[2,-2],[2,-1],[2,0],[2,1],[2,2]]

for h in range(H+4):
  for w in range(W+4):
    if S[h][w]=="#":
      ans[h][w]=-2

P = deque([[ch+1,cw+1]])
Q = deque([])

while P:
  x1,y1 = P.popleft()
  Q.append([x1,y1])
  for dx,dy in move:
    x = x1+dx
    y = y1+dy
    if ans[x][y]==-1:
      ans[x][y] = ans[x1][y1]
      P.append([x,y])
  
  if len(P)==0:
    while Q:
      x2,y2 = Q.popleft()
      for dx,dy in magic:
        x = x2+dx
        y = y2+dy
        if ans[x][y]==-1:
          ans[x][y] = ans[x2][y2]+1
          P.append([x,y])

print(ans[dh+1][dw+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
ch,cw = map(int,input().split())
dh,dw = map(int,input().split())
S = 2*[(W+4)*"#"]+["##"+input()+"##" for h in range(H)]+2*[(W+4)*"#"]
ans = [(W+4)*[-1] for h in range(H+4)]
ans[ch+1][cw+1] = 0
move = [[-1,0],[1,0],[0,-1],[0,1]]
magic = [[-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],[-1,-2],[-1,-1],[-1,1],[-1,2],[0,-2],[0,2],[1,-2],[1,-1],[1,1],[1,2],[2,-2],[2,-1],[2,0],[2,1],[2,2]]

for h in range(H+4):
  for w in range(W+4):
    if S[h][w]=="#":
      ans[h][w]=-2

P = deque([[ch+1,cw+1]])
Q = deque([])

while 0<len(P):
  x1,y1 = P.popleft()
  Q.append([x1,y1])
  for dx,dy in move:
    if ans[x1+dx][y1+dy]==-1:
      ans[x1+dx][y1+dy] = ans[x1][y1]
      P.append([x1+dx,y1+dy])
  
  if len(P)==0:
    while Q:
      x2,y2 = Q.popleft()
      for dx,dy in magic:
        if ans[x2+dx][y2+dy]==-1:
          ans[x2+dx][y2+dy] = ans[x2][y2]+1
          P.append([x2+dx,y2+dy])

print(ans[dh+1][dw+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
ch,cw = map(int,input().split())
dh,dw = map(int,input().split())
S = 2*[(W+4)*"#"]+["##"+input()+"##" for h in range(H)]+2*[(W+4)*"#"]
ans = [(W+4)*[-1] for h in range(H+4)]
ans[ch+1][cw+1] = 0
move = [[-1,0],[1,0],[0,-1],[0,1]]
magic = [[-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],[-1,-2],[-1,-1],[-1,1],[-1,2],[0,-2],[0,2],[1,-2],[1,-1],[1,1],[1,2],[2,-2],[2,-1],[2,0],[2,1],[2,2]]

for h in range(H+4):
  for w in range(W+4):
    if S[h][w]=="#":
      ans[h][w]=-2

P = deque([[ch+1,cw+1]])
Q = deque([])

while 0<len(P):
  x,y = P.popleft()
  Q.append([x,y])
  for dx,dy in move:
    if ans[x+dx][y+dy]==-1:
      ans[x+dx][y+dy] = ans[x][y]
      P.append([x+dx,y+dy])
  
  if len(P)==0:
    while Q:
      x,y = Q.popleft()
      for dx,dy in magic:
        if ans[x+dx][y+dy]==-1:
          ans[x+dx][y+dy] = ans[x][y]+1
          P.append([x+dx,y+dy])

print(ans[dh+1][dw+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
ch,cw = map(int,input().split())
dh,dw = map(int,input().split())
S = 2*[(W+4)*"#"]+["##"+input()+"##" for h in range(H)]+2*[(W+4)*"#"]
ans = [(W+4)*[-1] for h in range(H+4)]
ans[ch+1][cw+1] = 0
move = [[-1,0],[1,0],[0,-1],[0,1]]
magic = [[-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],[-1,-2],[-1,-1],[-1,1],[-1,2],[0,-2],[0,2],[1,-2],[1,-1],[1,1],[1,2],[2,-2],[2,-1],[2,0],[2,1],[2,2]]

for h in range(H+4):
  for w in range(W+4):
    if S[h][w]=="#":
      ans[h][w]=-2

P = deque([[ch+1,cw+1]])
Q = deque([])

while P:
  x,y = P.popleft()
  Q.append([x,y])
  for dx,dy in move:
    if ans[x+dx][y+dy]==-1:
      ans[x+dx][y+dy] = ans[x][y]
      P.append([x+dx,y+dy])
  
  if len(P)==0:
    while Q:
      x,y = Q.popleft()
      for dx,dy in magic:
        if ans[x+dx][y+dy]==-1:
          ans[x+dx][y+dy] = ans[x][y]+1
          P.append([x+dx,y+dy])

print(ans[dh+1][dw+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
ch,cw = map(int,input().split())
dh,dw = map(int,input().split())
S = 2*[(W+4)*"#"]+["##"+input()+"##" for h in range(H)]+2*[(W+4)*"#"]
ans = [(W+4)*[-1] for h in range(H+4)]
ans[ch+1][cw+1] = 0
move = [[-1,0],[1,0],[0,-1],[0,1]]
magic = [[-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],[-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],[0,-2],[0,-1],[0,0],[0,1],[0,2],[1,-2],[1,-1],[1,0],[1,1],[1,2],[2,-2],[2,-1],[2,0],[2,1],[2,2]]

for h in range(H+4):
  for w in range(W+4):
    if S[h][w]=="#":
      ans[h][w]=-2

P = deque([[ch+1,cw+1]])
Q = deque([])

while P:
  x,y = P.popleft()
  Q.append([x,y])
  for dx,dy in move:
    if ans[x+dx][y+dy]==-1:
      ans[x+dx][y+dy] = ans[x][y]
      P.append([x+dx,y+dy])
  
  if len(P)==0:
    while Q:
      x,y = Q.popleft()
      for dx,dy in magic:
        if ans[x+dx][y+dy]==-1:
          ans[x+dx][y+dy] = ans[x][y]+1
          P.append([x+dx,y+dy])

print(ans[dh+1][dw+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
CH,CW = map(int,input().split())
DH,DW = map(int,input().split())
S = 2*[(W+4)*["#"]]+[2*["#"]+list(input())+2*["#"] for h in range(H)]+2*[(W+4)*["#"]]
S[CH+1][CW+1] = 0
P = [[CH+1,CW+1]]
Q = deque([[CH+1,CW+1]])
D1 = [[1,0],[-1,0],[0,1],[0,-1]]
D2 = [[2,2],[2,1],[2,0],[2,-1],[2,-2],[1,2],[1,1],[1,-1],[1,-2],[0,2],[0,-2],[-1,2],[-1,1],[-1,-1],[-1,-2],[-2,2],[-2,1],[-2,0],[-2,-1],[-2,-2]]
ans = 0

while P:
  P = []
  while Q:
    edge = 0
    y,x = Q.popleft()
    for dy,dx in D1:
      if S[y+dy][x+dx]==".":
        S[y+dy][x+dx] = S[y][x]
        Q.append([y+dy,x+dx])
      elif S[y+dy][x+dx]=="#" and edge==0:
        edge+=1
        P.append([y,x])

  if S[DH+1][DW+1]!=".":
    print(S[DH+1][DW+1])
    exit()
  else:
    ans+=1
    for y,x in P:
      for dy,dx in D2:
        if S[y+dy][x+dx]==".":
          S[y+dy][x+dx] = ans
          Q.append([y+dy,x+dx])

if S[DH+1][DW+1]==".":
  print(-1)
else:
  print(S[DH+1][DW+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
CH,CW = map(int,input().split())
DH,DW = map(int,input().split())
S = 2*[(W+4)*["#"]]+[2*["#"]+list(input())+2*["#"] for h in range(H)]+2*[(W+4)*["#"]]
S[CH+1][CW+1] = 0
P = [[CH+1,CW+1]]
Q = deque([[CH+1,CW+1]])
ans = 0

while P:
  P = []
  while Q:
    edge = 0
    y,x = Q.popleft()
    for dy,dx in [[1,0],[-1,0],[0,1],[0,-1]]:
      if S[y+dy][x+dx]==".":
        S[y+dy][x+dx] = S[y][x]
        Q.append([y+dy,x+dx])
      elif S[y+dy][x+dx]=="#":
        edge+=1
        if 2<=edge:
          edge = -1
          P.append([y,x])

  if S[DH+1][DW+1]!=".":
    print(S[DH+1][DW+1])
    exit()
  else:
    ans+=1
    for y,x in P:
      for dy,dx in [[2,2],[2,1],[2,0],[2,-1],[2,-2],[1,2],[1,1],[1,-1],[1,-2],[0,2],[0,-2],[-1,2],[-1,1],[-1,-1],[-1,-2],[-2,2],[-2,1],[-2,0],[-2,-1],[-2,-2]]:
        if S[y+dy][x+dx]==".":
          S[y+dy][x+dx] = ans
          Q.append([y+dy,x+dx])

if S[DH+1][DW+1]==".":
  print(-1)
else:
  print(S[DH+1][DW+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Time Limit Exceeded):
from collections import *
H,W = map(int,input().split())
CH,CW = map(int,input().split())
DH,DW = map(int,input().split())
S = 2*[(W+4)*["#"]]+[2*["#"]+list(input())+2*["#"] for h in range(H)]+2*[(W+4)*["#"]]
S[CH+1][CW+1] = 0
P = [[CH+1,CW+1]]
Q = deque([[CH+1,CW+1]])
ans = 0

while P:
  P = []
  while Q:
    y,x = Q.popleft()
    P+=[[y,x]]
    for dy,dx in [[1,0],[-1,0],[0,1],[0,-1]]:
      if S[y+dy][x+dx]==".":
        S[y+dy][x+dx] = S[y][x]
        Q+=[[y+dy,x+dx]]

  if S[DH+1][DW+1]!=".":
    print(S[DH+1][DW+1])
    exit()
  else:
    ans+=1
    for y,x in P:
      for dy,dx in [[2,2],[2,1],[2,0],[2,-1],[2,-2],[1,2],[1,1],[1,-1],[1,-2],[0,2],[0,-2],[-1,2],[-1,1],[-1,-1],[-1,-2],[-2,2],[-2,1],[-2,0],[-2,-1],[-2,-2]]:
        if S[y+dy][x+dx]==".":
          S[y+dy][x+dx] = ans
          Q+=[[y+dy,x+dx]]

if S[DH+1][DW+1]==".":
  print(-1)
else:
  print(S[DH+1][DW+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()

Buggy python submission (verdict: Runtime Error):
from collections import *
H,W = map(int,input().split())
CH,CW = map(int,input().split())
DH,DW = map(int,input().split())
S = [(W+4)*["#"]]+[(W+4)*["#"]]+[2*["#"]+list(input())+2*["#"] for h in range(H)]+[(W+4)*["#"]]+[(W+4)*["#"]]
S[CH+1][CW+1] = 0
P = []
Q = deque([[CH+1,CW+1]])
ans = 0

for n in range(1000):
  while Q:
    y,x = Q.popleft()
    P+=[[y,x]]
    for dy,dx in [[1,0],[-1,0],[0,1],[0,-1]]:
      if S[y+dy][x+dx]==".":
        S[y+dy][x+dx] = S[y][x]
        Q+=[[y+dy,x+dx]]

  if S[DH+1][DW+1]==".":
    for x,y in P:
      for dy,dx in [[2,2],[2,1],[2,0],[2,-1],[2,-2],[1,2],[1,1],[1,-1],[1,-2],[0,2],[0,-2],[-1,2],[-1,1],[-1,-1],[-1,-2],[-2,2],[-2,1],[-2,0],[-2,-1],[-2,-2]]:
        if S[y+dy][x+dx]==".":
          S[y+dy][x+dx] = ans+1
          Q+=[[y+dy,x+dx]]
    ans+=1

if S[DH+1][DW+1]==".":
  print(-1)
else:
  print(S[DH+1][DW+1])

Fixed submission:
from collections import *

def main():
    H,W = map(int, input().split())
    ch,cw = map(int, input().split())
    dh,dw = map(int, input().split())
    s = ["#"*(W+4)]
    s.append("#"*(W+4))
    for i in range(H):
        s.append("##"+input()+"##")
    s.append("#"*(W+4))
    s.append("#"*(W+4))
    
    ans = [[-1]*(W+4) for _ in range(H+4)]
    for i in range(H+4):
        for j in range(W+4):
            if s[i][j] == "#":
                ans[i][j] = -2
    ch += 1; cw += 1
    dh += 1; dw += 1
    ans[ch][cw] = 0
    
    move = [[-1,0],[1,0],[0,-1],[0,1]]
    magic = [
        [-2,-2],[-2,-1],[-2,0],[-2,1],[-2,2],\
        [-1,-2],[-1,-1],[-1,0],[-1,1],[-1,2],\
        [0,-2],[0,-1],[0,0],[0,1],[0,2],\
        [1,-2],[1,-1],[1,0],[1,1],[1,2],\
        [2,-2],[2,-1],[2,0],[2,1],[2,2]
        ]
    
    mylist = deque([[ch,cw]])
    mylist2 = deque([])
    while len(mylist) > 0:
        x,y = mylist.popleft()
        mylist2.append([x,y])
        for p,q in move:
            v1,v2 = x+p,y+q
            if ans[v1][v2] == -1:
                mylist.append([v1,v2])
                ans[v1][v2] = ans[x][y]
        if len(mylist) == 0:
            while len(mylist2) > 0:
                x2,y2 = mylist2.popleft()
                for v1,v2 in magic:
                    i,j = x2+v1,y2+v2
                    if ans[i][j] == -1:
                        ans[i][j] = ans[x2][y2]+1
                        mylist.append([i,j])
    print(ans[dh][dw])
 
if __name__ == "__main__":
    main()