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:

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

Example 2:

**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.

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