Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
input = sys.stdin.readline
h,w,k=map(int,input().split())
a = [list(input().rstrip()) for i in range(h)]
q = deque()
for i in range(h):
  for j in range(w):
    if a[i][j] == "#":
      a[i][j] = 0
      q.append((i,j,0))
    else:
      a[i][j] = -1
while q:
  s,t,cnt = q.popleft()
  for ns,nt in ((s+1,t),(s-1,t),(s,t+1),(s,t-1)):
    if 0<=ns<=h-1 and 0<=nt<=w-1 and a[ns][nt] == -1:
      q.append((ns,nt,cnt+1))
      a[ns][nt] = cnt+1
ans = 0
for i in range(h):
  for j in range(w):
    ans = max(ans,a[i][j])
print(ans)

Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
input = sys.stdin.readline
h,w,k=map(int,input().split())
a = [list(input().rstrip()) for i in range(h)]
q = deque()
for i in range(h):
  for j in range(w):
    if a[i][j] == "x":
      a[i][j] = 0
      q.append((i,j,0))
    else:
      a[i][j] = -1
while q:
  s,t,cnt = q.popleft()
  for ns,nt in ((s+1,t),(s-1,t),(s,t+1),(s,t-1)):
    if 0<=ns<=h-1 and 0<=nt<=w-1 and a[ns][nt] == -1:
      q.append((ns,nt,cnt+1))
      a[ns][nt] = cnt+1
ans = 0
for i in range(k-1,h-k+1):
  for j in range(k-1,w-k+1):
    if a[i][j] >= k:
      ans += 1
print(ans)

Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
import numpy as np
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [list(input()) for i in range(h)]
b = np.zeros((h,w).dtype=int64)
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            q.append([i,j,0])
        else:
            b[i][j]=-1
"""
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and a[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        a[s-1][t] = cnt+1
    if s<h-1 and a[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        a[s+1][t] = cnt+1
    if t>0 and a[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        a[s][t-1] = cnt+1
    if t<w-1 and a[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        a[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(a[i]))
print(ans)
"""


Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
import numpy as np
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [list(input()) for i in range(h)]
b = np.zeros(h,w.dtype=int64)
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            q.append([i,j,0])
        else:
            b[i][j]=-1
"""
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and a[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        a[s-1][t] = cnt+1
    if s<h-1 and a[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        a[s+1][t] = cnt+1
    if t>0 and a[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        a[s][t-1] = cnt+1
    if t<w-1 and a[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        a[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(a[i]))
print(ans)
"""


Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [list(input()) for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            a[i][j]=0
            q.append([i,j,0])
        else:
            a[i][j]=-1
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and a[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        a[s-1][t] = cnt+1
    if s<h-1 and a[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        a[s+1][t] = cnt+1
    if t>0 and a[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        a[s][t-1] = cnt+1
    if t<w-1 and a[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        a[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(a[i]))
print(ans)


Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            a[i][j]=0
            q.append([i,j,0])
        else:
            a[i][j]=-1
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and a[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        a[s-1][t] = cnt+1
    if s<h-1 and a[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        a[s+1][t] = cnt+1
    if t>0 and a[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        a[s][t-1] = cnt+1
    if t<w-1 and a[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        a[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(a[i]))
print(ans)


Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [list(input()) for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            a[i][j] = 0
            q.append([i,j,0])
        else:
            a[i][j] = -1
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and a[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        a[s-1][t] = cnt+1
    if s<h-1 and a[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        a[s+1][t] = cnt+1
    if t>0 and a[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        a[s][t-1] = cnt+1
    if t<w-1 and a[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        a[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(a[i]))
print(ans)

Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [list(input()) for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            a[i][j] = 0
            q.append([i,j,0])
        else:
            a[i][j] = -1
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        a[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        a[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        a[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        a[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(a[i]))
print(ans)

Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Runtime Error):
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            a[i][j] = 0
            q.append([i,j,0])
        else:
            a[i][j] = -1
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        a[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        a[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        a[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        a[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(a[i]))
print(ans)

Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)

Fixed submission:
from collections import deque
import sys
input = sys.stdin.readline
h,w=map(int, input().split(' '))
a = [input() for i in range(h)]
nl = [[] for i in range(h)]
q = deque()
for i in range(h):
    for j in range(w):
        if a[i][j] == "#":
            nl[i].append(0)
            q.append([i,j,0])
        else:
            nl[i].append(-1)
while q:
    [s,t,cnt] = q.popleft()
    if s>0 and nl[s-1][t] == -1:
        q.append([s-1,t,cnt+1])
        nl[s-1][t] = cnt+1
    if s<h-1 and nl[s+1][t] == -1:
        q.append([s+1,t,cnt+1])
        nl[s+1][t] = cnt+1
    if t>0 and nl[s][t-1] == -1:
        q.append([s,t-1,cnt+1])
        nl[s][t-1] = cnt+1
    if t<w-1 and nl[s][t+1] == -1:
        q.append([s,t+1,cnt+1])
        nl[s][t+1] = cnt+1
ans = 0
for i in range(h):
    ans = max(ans,max(nl[i]))
print(ans)