• Home
• com.github.javadev
• leetcode-in-java
• 1.23
• source code
• readme.md

×

Project download

Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance.
Project price only 1 $

You can buy this project and download/modify it how often you want.

g2601_2700.s2625_flatten_deeply_nested_array.readme.md Maven / Gradle / Ivy

2625\. Flatten Deeply Nested Array

Medium

Given a **multi-dimensional** array `arr` and a depth `n`, return a **flattened** version of that array.

A **multi-dimensional** array is a recursive data structure that contains integers or other **multi-dimensional** arrays.

A **flattened** array is a version of that array with some or all of the sub-arrays removed and replaced with the actual elements in that sub-array. This flattening operation should only be done if the current depth of nesting is less than `n`. The depth of the elements in the first array are considered to be `0`.

Please solve it without the built-in `Array.flat` method.

**Example 1:**

**Input** arr = [1, 2, 3, [4, 5, 6], [7, 8, [9, 10, 11], 12], [13, 14, 15]] n = 0

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

**Explanation:** Passing a depth of n=0 will always result in the original array. This is because the smallest possible depth of a subarray (0) is not less than n=0. Thus, no subarray should be flattened.

**Example 2:**

**Input** arr = [1, 2, 3, [4, 5, 6], [7, 8, [9, 10, 11], 12], [13, 14, 15]] n = 1

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

**Explanation:** The subarrays starting with 4, 7, and 13 are all flattened. This is because their depth of 0 is less than 1. However [9, 10, 11] remains unflattened because its depth is 1.

**Example 3:**

**Input** arr = [[1, 2, 3], [4, 5, 6], [7, 8, [9, 10, 11], 12], [13, 14, 15]] n = 2

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

**Explanation:** The maximum depth of any subarray is 1. Thus, all of them are flattened.

**Constraints:**

*   0 <= count of numbers in arr <= 105
*   0 <= count of subarrays in arr <= 105
*   `maxDepth <= 1000`
*   `-1000 <= each number <= 1000`
*   `0 <= n <= 1000`