有人可以向我解释第二个循环..我已经理解了第一个...谢谢

I'm creating a java project called magicsquare and I've searched online on how to do it. Now, I'm trying to understand how the 2nd loop works, I know that it prints and align the magic square, but I don't know the details. I already know the first one. I would really appreciate if someone explains to me the 2nd loop. Thanks!I'm creating a java project called magicsquare