题解 | 矩阵计算
矩阵计算
https://www.nowcoder.com/practice/0c83231923c541d2aa15861571831ee5
n,m = map(int, input().split())
a = [list(map(int, input().split())) for i in range(n)]
sum = 0
for j in range(n):
for y in a[j]:
if y > 0:
sum += y
print(sum)
