for循环的缩进问题

Question

a=[[1,2,3],[4,5,6],[7,8,9]]
s=0 for c in a:
for j in range(3):
s+=c[j]print(s)

请问怎么算？

Answer 1

a = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
s = 0
for c in a:
    for j in range(3):
        s += c[j]
    print(s)