Envío 1492

Código

import math

[r, c] = map(int, input().split())
m = []
for i in range(0, r):
    m += list(map(int, input().split(" ")))

max_sum = -math.inf

for r1 in range(0, r):
    for c1 in range(0, c):
        for r2 in range(r1 + 1, r + 1):
            for c2 in range(c1 + 1, c + 1):
                sub_sum = 0
                for r3 in range(r1, r2):
                    for c3 in range(c1, c2):
                        sub_sum += m[r3 * c + c3]
                max_sum = max(max_sum, sub_sum)
print(max_sum)