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

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
dq=deque()
dq.append((0,si,sj))
ok=False
while dq:
    k,i,j=dq.popleft()
    if i==ti and j==tj:
        ok=True
        break
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                append=dq.appendleft
                nk=k
            else:
                append=dq.append
                nk=k+1
            if k>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            append((nk,ni,nj))
      
if ok:
    ans=dist[ti][tj]
else:
    ans=-1

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    dist[i][j]=k
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            heappush(hp,(nk,ni,nj))

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Runtime Error):
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    dist[ni][nj]=nk
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            heappush(hp,(nk,ni,nj))

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]

big=10**9
A=[]
for row in sys.stdin:
    A.append([big if x=='.' else '#' for x in row])
A[si][sj]=0

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if (abs(di)==1 and dj==0) or (di==0 and abs(dj)==1):
                nk=k
            else:
                nk=k+1
            if nk>=A[ni][nj]:
                continue
            A[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,+2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if (abs(di)==1 and dj==0) or (di==0 and abs(dj)==1):
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,+2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if (abs(di)==1 and dj==0) or (di==0 and abs(dj)==1):
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import *
from pprint import pprint

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dx=[-2,-1,0,1,+2]
dy=[-2,-1,0,1,+2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    for ci in dy:
        for cj in dx:
            if ci==cj==0:
                continue
            ni,nj=i+ci,j+cj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if (abs(ci)==1 and cj==0) or (ci==0 and abs(cj)==1):
                x=k
            else:
                x=k+1
            if x>=dist[ni][nj]:
                continue
            dist[ni][nj]=x
            heappush(hp,(x,ni,nj))


#pprint(dist)

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
import sys
from heapq import *
from pprint import pprint

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dx=[-2,-1,0,1,+2]
dy=[-2,-1,0,1,+2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    for ci in dy:
        for cj in dx:
            if ci==cj==0:
                continue
            ni,nj=i+ci,j+cj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if (abs(ci)==1 and cj==0) or (ci==0 and abs(cj)==1):
                x=k
            else:
                x=k+1
            if x>=dist[ni][nj]:
                continue
            dist[ni][nj]=x
            heappush(hp,(x,ni,nj))


#pprint(dist)

print(ans)


Fixed submission:
import sys
from heapq import *

H,W=map(int,input().split())
si,sj=[int(x)-1 for x in input().split()]
ti,tj=[int(x)-1 for x in input().split()]
A=list(sys.stdin)

ans=-1
hp=[(0,si,sj)]
dirs=[-2,-1,0,1,2]
dist=[[float('inf')]*W for _ in range(H)]
dist[si][sj]=0
while hp:
    k,i,j=heappop(hp)
    if i==ti and j==tj:
        ans=k
        break
    if k>dist[i][j]:
        continue
    for di in dirs:
        for dj in dirs:
            if di==dj==0:
                continue
            ni,nj=i+di,j+dj
            if not (0<=ni<H and 0<=nj<W):
                continue
            if A[ni][nj]=='#':
                continue
            if abs(di)+abs(dj)==1:
                nk=k
            else:
                nk=k+1
            if nk>=dist[ni][nj]:
                continue
            dist[ni][nj]=nk
            heappush(hp,(nk,ni,nj))

print(ans)