# 1424. Diagonal Traverse II

<https://leetcode.com/problems/diagonal-traverse-ii>

## Description

Given a list of lists of integers, `nums`, return all elements of `nums` in diagonal order as shown in the below images. **Example 1:**

![](https://assets.leetcode.com/uploads/2020/04/08/sample_1_1784.png)

```
**Input:** nums = [[1,2,3],[4,5,6],[7,8,9]]
**Output:** [1,4,2,7,5,3,8,6,9]
```

**Example 2:**

![](https://assets.leetcode.com/uploads/2020/04/08/sample_2_1784.png)

```
**Input:** nums = [[1,2,3,4,5],[6,7],[8],[9,10,11],[12,13,14,15,16]]
**Output:** [1,6,2,8,7,3,9,4,12,10,5,13,11,14,15,16]
```

**Example 3:**

```
**Input:** nums = [[1,2,3],[4],[5,6,7],[8],[9,10,11]]
**Output:** [1,4,2,5,3,8,6,9,7,10,11]
```

**Example 4:**

```
**Input:** nums = [[1,2,3,4,5,6]]
**Output:** [1,2,3,4,5,6]
```

**Constraints:**

* `1 <= nums.length <= 10^5`
* `1 <= nums[i].length <= 10^5`
* `1 <= nums[i][j] <= 10^9`
* There at most `10^5` elements in `nums`.

## ac

```java
```