自己测试没问题啊
python代码水平不高，求帮助!!!

h, l = map(int, input().split())
y = []
for i in range(h):
    t = input()
    y.append(t)
index = 0
s = 0
for item in y:
    item = item.split()
    item = [int(i) for i in item]
    if index == 0 or index == l-1:
        s += sum(item)
    else:
        if l == 1:
            s += sum(item)
        else:
            s = s + item[0] + item[-1]
    index += 1
print(s)