Buggy python submission (verdict: Time Limit Exceeded):
import sys
X, Y, U = [], [], []
if True:
    H, W, *nums = map(int, sys.stdin.read().split())
    i = 0
    for _ in range(H):
        X.append(nums[i:i + W])
        i += W
        U.append([set() for _ in range(W)])
    for _ in range(H):
        Y.append(nums[i:i + W])
        i += W
else:
    H, W = map(int, input().split())
    for _ in range(H):
        X.append(list(map(int, input().split())))
        U.append([set() for _ in range(W)])
    for _ in range(H):
        Y.append(list(map(int, input().split())))

U[0][0] = set([ abs(X[0][0] - Y[0][0]) ])

for i in range(W):
    for j in range(H):
        for k in U[j][i]:
            if j + 1 < H:
                x = abs(X[j + 1][i] - Y[j + 1][i])
                U[j + 1][i].update([abs(k + x), abs(k - x)])
            if i + 1 < W:
                x = abs(X[j][i + 1] - Y[j][i + 1])
                U[j][i + 1].update([abs(k + x), abs(k - x)])
print(min(U[-1][-1]))

Fixed submission:
# at ABC 147 e (500)
import sys
X, Y, U = [], [], []
if True:
    H, W, *nums = map(int, sys.stdin.read().split())
    i = 0
    for _ in range(H):
        X.append(nums[i:i + W])
        i += W
        U.append([0] * W)
    for _ in range(H):
        Y.append(nums[i:i + W])
        i += W
else:    
    H, W = map(int, input().split())
    for _ in range(H):
        X.append(list(map(int, input().split())))
        U.append([0 for _ in range(W)])
    for _ in range(H):
        Y.append(list(map(int, input().split())))

mid = 80*80

init = abs(X[0][0] - Y[0][0])
U[0][0] = (1 << (mid - init)) | (1 << (mid + init))

for i in range(W):
    for j in range(H):
        k = abs(X[j][i] - Y[j][i])
        if j > 0:
            U[j][i] |= (U[j - 1][i] << k)
            U[j][i] |= (U[j - 1][i] >> k)
        if i > 0:
            U[j][i] |= (U[j][i - 1] << k)
            U[j][i] |= (U[j][i - 1] >> k)
#        U[j][i] = U[j][i] & ((1 << (2 * mid)) - 1)
    
i = 0
min_ = float("inf")
while True:
     if U[-1][-1] & 1:
         min_ = min(min_, abs(i - mid))
     U[-1][-1] = U[-1][-1] >> 1
     i += 1
     if i >= 2 * mid:
         break
print(min_)

Buggy python submission (verdict: Time Limit Exceeded):
H, W = map(int, input().split())
X, Y, U = [], [], []
for _ in range(H):
    X.append(list(map(int, input().split())))
    U.append([set() for _ in range(W)])
for _ in range(H):
    Y.append(list(map(int, input().split())))

U[0][0] = set([ abs(X[0][0] - Y[0][0]) ])

for i in range(W):
    for j in range(H):
        for k in U[j][i]:
            if j + 1 < H:
                x = abs(X[j + 1][i] - Y[j + 1][i])
                U[j + 1][i].update([abs(k + x), abs(k - x)])
            if i + 1 < W:
                x = abs(X[j][i + 1] - Y[j][i + 1])
                U[j][i + 1].update([abs(k + x), abs(k - x)])
print(min(U[-1][-1]))

Fixed submission:
# at ABC 147 e (500)
import sys
X, Y, U = [], [], []
if True:
    H, W, *nums = map(int, sys.stdin.read().split())
    i = 0
    for _ in range(H):
        X.append(nums[i:i + W])
        i += W
        U.append([0] * W)
    for _ in range(H):
        Y.append(nums[i:i + W])
        i += W
else:    
    H, W = map(int, input().split())
    for _ in range(H):
        X.append(list(map(int, input().split())))
        U.append([0 for _ in range(W)])
    for _ in range(H):
        Y.append(list(map(int, input().split())))

mid = 80*80

init = abs(X[0][0] - Y[0][0])
U[0][0] = (1 << (mid - init)) | (1 << (mid + init))

for i in range(W):
    for j in range(H):
        k = abs(X[j][i] - Y[j][i])
        if j > 0:
            U[j][i] |= (U[j - 1][i] << k)
            U[j][i] |= (U[j - 1][i] >> k)
        if i > 0:
            U[j][i] |= (U[j][i - 1] << k)
            U[j][i] |= (U[j][i - 1] >> k)
#        U[j][i] = U[j][i] & ((1 << (2 * mid)) - 1)
    
i = 0
min_ = float("inf")
while True:
     if U[-1][-1] & 1:
         min_ = min(min_, abs(i - mid))
     U[-1][-1] = U[-1][-1] >> 1
     i += 1
     if i >= 2 * mid:
         break
print(min_)

Buggy python submission (verdict: Time Limit Exceeded):
H, W = map(int, input().split())
X, Y, U = [], [], []
for _ in range(H):
    X.append(list(map(int, input().split())))
    U.append([set() for _ in range(W)])
for _ in range(H):
    Y.append(list(map(int, input().split())))

U[0][0] = set([ abs(X[0][0] - Y[0][0]) ])

for i in range(W):
    for j in range(H):
        for k in U[j][i]:
            if j + 1 < H:
                U[j + 1][i].add(abs(k + abs(X[j + 1][i] - Y[j + 1][i])))
                U[j + 1][i].add(abs(k - abs(X[j + 1][i] - Y[j + 1][i])))
            if i + 1 < W:
                U[j][i + 1].add(abs(k + abs(X[j][i + 1] - Y[j][i + 1])))
                U[j][i + 1].add(abs(k - abs(X[j][i + 1] - Y[j][i + 1])))
print(min(U[-1][-1]))

Fixed submission:
# at ABC 147 e (500)
import sys
X, Y, U = [], [], []
if True:
    H, W, *nums = map(int, sys.stdin.read().split())
    i = 0
    for _ in range(H):
        X.append(nums[i:i + W])
        i += W
        U.append([0] * W)
    for _ in range(H):
        Y.append(nums[i:i + W])
        i += W
else:    
    H, W = map(int, input().split())
    for _ in range(H):
        X.append(list(map(int, input().split())))
        U.append([0 for _ in range(W)])
    for _ in range(H):
        Y.append(list(map(int, input().split())))

mid = 80*80

init = abs(X[0][0] - Y[0][0])
U[0][0] = (1 << (mid - init)) | (1 << (mid + init))

for i in range(W):
    for j in range(H):
        k = abs(X[j][i] - Y[j][i])
        if j > 0:
            U[j][i] |= (U[j - 1][i] << k)
            U[j][i] |= (U[j - 1][i] >> k)
        if i > 0:
            U[j][i] |= (U[j][i - 1] << k)
            U[j][i] |= (U[j][i - 1] >> k)
#        U[j][i] = U[j][i] & ((1 << (2 * mid)) - 1)
    
i = 0
min_ = float("inf")
while True:
     if U[-1][-1] & 1:
         min_ = min(min_, abs(i - mid))
     U[-1][-1] = U[-1][-1] >> 1
     i += 1
     if i >= 2 * mid:
         break
print(min_)