What will be the time complexity of the following nested loop:

for(int i=2;i<n;++i){
    for(int j=i;j<n;j+=i){
        //some code here
    }
}

Actually I was participating in a competition on Codechef last night. And there was a question for which I thought of a solution like this. But the range of n was [2, 10⁶] and time limit was 1.5s. So I thought that my solution will exceed the time limit and hence I didn't submit it. But after the contest I saw another guy submitting the same solution and getting his solution accepted. So, can someone tell what is the exact time complexity of this code snippet?

Link for question

Thanks in advance

Given a square array of size N × N where each cell is filled with a number between  - 9 and 9. A sub square of size k is any set of k contiguous columns and k contiguous rows. For any sub square, the sum of elements in its cells is called a sub square sum. Given the N × N square, write a program to find the maximum sub square sum. (Note that a 1 × 1 square (k = 1) is not considered a sub square)

Constraints: 2 ≤ N ≤ 1000

By looking at the constraints I think we have to do it in O(N²). I could manage to reach to O(N³). Please Help

Thanks in advance

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