Buggy python submission (verdict: Runtime Error):
h,w = map(int, input().split())
a = [list(map(int, input().split())) for _ in range(h)]
b = [list(map(int, input().split())) for _ in range(h)]
g = [[0]*w for _ in range(h)]
for i in range(h):
  for j in range(w):
    g[i][j] = abs(a[i][j] - b[i][j])
a = b = 0
m = max(max(x) for x in g)*(h+w)//2 + 1
dp = [[[False]*m for _ in range(w+1)] for _ in range(h+1)]
dp[0][1][0] = True
dp[1][0][0] = True
for i in range(1,h+1):
  for j in range(1,w+1):
    for x in range(m):
      if dp[i-1][j][x] or dp[i][j-1][x]:
        dp[i][j][abs(x-g[i-1][j-1])] |= True
        if x + g[i-1][j-1] < 3000:
            dp[i][j][x+g[i-1][j-1]] |= True
for x in range(m):
  if dp[h][w][x]:
    print(x)
    break


Fixed submission:
def fold(x,m):
    y = 0
    for _ in range(m):
        y |= x&1
        y <<= 1
        x >>= 1
    return x|y

lmi = lambda: list(map(int, input().split()))

h,w = lmi()
a = [lmi() for _ in range(2*h)]
g = [[abs(a[i][j] - a[i+h][j]) for j in range(w)] for i in range(h)]

mask = (1<<12801) - 1

dp = [[0]*(w+1) for _ in range(h+1)]
dp[0][0] = 1
for i in range(h):
  for j in range(w):
    cur,par = g[i][j],dp[i][j]
    pos = (par<<cur)|fold(par,cur)
    pos &= mask
    dp[i+1][j] |= pos
    dp[i][j+1] |= pos
for i in range(12801):
  if dp[-1][-2]&(1<<i):
    print(i)
    break

Buggy python submission (verdict: Runtime Error):
h,w = map(int, input().split())
a = [list(map(int, input().split())) for _ in range(h)]
b = [list(map(int, input().split())) for _ in range(h)]
g = [[0]*w for _ in range(h)]
for i in range(h):
  for j in range(w):
    g[i][j] = abs(a[i][j] - b[i][j])
a = b = 0
m = max(max(x) for x in g)*(h+w)
dp = [[[False]*m for _ in range(w+1)] for _ in range(h+1)]
dp[0][1][0] = True
dp[1][0][0] = True
for i in range(1,h+1):
  for j in range(1,w+1):
    for x in range(m):
      if dp[i-1][j][x] or dp[i][j-1][x]:
        dp[i][j][abs(x-g[i-1][j-1])] |= True
        if x + g[i-1][j-1] < 3000:
            dp[i][j][x+g[i-1][j-1]] |= True
for x in range(m):
  if dp[h][w][x]:
    print(x)
    break


Fixed submission:
def fold(x,m):
    y = 0
    for _ in range(m):
        y |= x&1
        y <<= 1
        x >>= 1
    return x|y

lmi = lambda: list(map(int, input().split()))

h,w = lmi()
a = [lmi() for _ in range(2*h)]
g = [[abs(a[i][j] - a[i+h][j]) for j in range(w)] for i in range(h)]

mask = (1<<12801) - 1

dp = [[0]*(w+1) for _ in range(h+1)]
dp[0][0] = 1
for i in range(h):
  for j in range(w):
    cur,par = g[i][j],dp[i][j]
    pos = (par<<cur)|fold(par,cur)
    pos &= mask
    dp[i+1][j] |= pos
    dp[i][j+1] |= pos
for i in range(12801):
  if dp[-1][-2]&(1<<i):
    print(i)
    break

Buggy python submission (verdict: Time Limit Exceeded):
h,w = map(int, input().split())
a = [list(map(int, input().split())) for _ in range(h)]
b = [list(map(int, input().split())) for _ in range(h)]
g = [[0]*w for _ in range(h)]
for i in range(h):
  for j in range(w):
    g[i][j] = abs(a[i][j] - b[i][j])
a = b = 0
dp = [[[False]*6400 for _ in range(w+1)] for _ in range(h+1)]
dp[0][1][0] = True
dp[1][0][0] = True
for i in range(1,h+1):
  for j in range(1,w+1):
    for x in range(6400):
      if dp[i-1][j][x] or dp[i][j-1][x]:
        dp[i][j][abs(x-g[i-1][j-1])] |= True
        if x + g[i-1][j-1] < 6400:
            dp[i][j][x+g[i-1][j-1]] |= True
for x in range(6400):
  if dp[h][w][x]:
    print(x)
    break


Fixed submission:
def fold(x,m):
    y = 0
    for _ in range(m):
        y |= x&1
        y <<= 1
        x >>= 1
    return x|y

lmi = lambda: list(map(int, input().split()))

h,w = lmi()
a = [lmi() for _ in range(2*h)]
g = [[abs(a[i][j] - a[i+h][j]) for j in range(w)] for i in range(h)]

mask = (1<<12801) - 1

dp = [[0]*(w+1) for _ in range(h+1)]
dp[0][0] = 1
for i in range(h):
  for j in range(w):
    cur,par = g[i][j],dp[i][j]
    pos = (par<<cur)|fold(par,cur)
    pos &= mask
    dp[i+1][j] |= pos
    dp[i][j+1] |= pos
for i in range(12801):
  if dp[-1][-2]&(1<<i):
    print(i)
    break