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# 1031. Maximum Sum of Two Non-Overlapping Subarrays

<https://leetcode.com/problems/maximum-sum-of-two-non-overlapping-subarrays>

## Description

Given an integer array `nums` and two integers `firstLen` and `secondLen`, return *the maximum sum of elements in two non-overlapping **subarrays** with lengths* `firstLen` *and* `secondLen`.

The array with length `firstLen` could occur before or after the array with length `secondLen`, but they have to be non-overlapping.

A **subarray** is a **contiguous** part of an array.

**Example 1:**

```
**Input:** nums = [0,6,5,2,2,5,1,9,4], firstLen = 1, secondLen = 2
**Output:** 20
**Explanation:** One choice of subarrays is [9] with length 1, and [6,5] with length 2.
```

**Example 2:**

```
**Input:** nums = [3,8,1,3,2,1,8,9,0], firstLen = 3, secondLen = 2
**Output:** 29
**Explanation:** One choice of subarrays is [3,8,1] with length 3, and [8,9] with length 2.
```

**Example 3:**

```
**Input:** nums = [2,1,5,6,0,9,5,0,3,8], firstLen = 4, secondLen = 3
**Output:** 31
**Explanation:** One choice of subarrays is [5,6,0,9] with length 4, and [3,8] with length 3.
```

**Constraints:**

* `1 <= firstLen, secondLen <= 1000`
* `2 <= firstLen + secondLen <= 1000`
* `firstLen + secondLen <= nums.length <= 1000`
* `0 <= nums[i] <= 1000`

## ac

```java
```