# 0364. Nested List Weight Sum II

<https://leetcode.com/problems/nested-list-weight-sum-ii>

## Description

You are given a nested list of integers `nestedList`. Each element is either an integer or a list whose elements may also be integers or other lists.

The **depth** of an integer is the number of lists that it is inside of. For example, the nested list `[1,[2,2],[[3],2],1]` has each integer's value set to its **depth**. Let `maxDepth` be the **maximum depth** of any integer.

The **weight** of an integer is `maxDepth - (the depth of the integer) + 1`.

Return *the sum of each integer in* `nestedList` *multiplied by its **weight***.

**Example 1:**

![](https://assets.leetcode.com/uploads/2021/03/27/nestedlistweightsumiiex1.png)

```
**Input:** nestedList = [[1,1],2,[1,1]]
**Output:** 8
**Explanation:** Four 1's with a weight of 1, one 2 with a weight of 2.
1*1 + 1*1 + 2*2 + 1*1 + 1*1 = 8
```

**Example 2:**

![](https://assets.leetcode.com/uploads/2021/03/27/nestedlistweightsumiiex2.png)

```
**Input:** nestedList = [1,[4,[6]]]
**Output:** 17
**Explanation:** One 1 at depth 3, one 4 at depth 2, and one 6 at depth 1.
1*3 + 4*2 + 6*1 = 17
```

**Constraints:**

* `1 <= nestedList.length <= 50`
* The values of the integers in the nested list is in the range `[-100, 100]`.
* The maximum **depth** of any integer is less than or equal to `50`.

## ac

```java
class Solution {
    public int depthSumInverse(List<NestedInteger> nestedList) {
        int unweighted = 0, res = 0;
        while (nestedList.size() > 0) {
            List<NestedInteger> next = new ArrayList<>();
            for (NestedInteger ni : nestedList) {
                if (ni.isInteger()) unweighted += ni.getInteger();
                else next.addAll(ni.getList());
            }
            res += unweighted;
            nestedList = next;
        }

        return res;
    }
}

/*
1) use 2 vars: weighted/unweighted; 2) recursion until no more list, each time += unweighted, as they go one level further, they add once more;
*/
```


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://jaywin.gitbook.io/leetcode/solutions/0364-nested-list-weight-sum-ii.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.