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# 1674. Minimum Moves to Make Array Complementary

<https://leetcode.com/problems/minimum-moves-to-make-array-complementary>

## Description

You are given an integer array `nums` of **even** length `n` and an integer `limit`. In one move, you can replace any integer from `nums` with another integer between `1` and `limit`, inclusive.

The array `nums` is **complementary** if for all indices `i` (**0-indexed**), `nums[i] + nums[n - 1 - i]` equals the same number. For example, the array `[1,2,3,4]` is complementary because for all indices `i`, `nums[i] + nums[n - 1 - i] = 5`.

Return the ***minimum** number of moves required to make* `nums` ***complementary***.

**Example 1:**

```
**Input:** nums = [1,2,4,3], limit = 4
**Output:** 1
**Explanation:** In 1 move, you can change nums to [1,2,2,3] (underlined elements are changed).
nums[0] + nums[3] = 1 + 3 = 4.
nums[1] + nums[2] = 2 + 2 = 4.
nums[2] + nums[1] = 2 + 2 = 4.
nums[3] + nums[0] = 3 + 1 = 4.
Therefore, nums[i] + nums[n-1-i] = 4 for every i, so nums is complementary.
```

**Example 2:**

```
**Input:** nums = [1,2,2,1], limit = 2
**Output:** 2
**Explanation:** In 2 moves, you can change nums to [2,2,2,2]. You cannot change any number to 3 since 3 > limit.
```

**Example 3:**

```
**Input:** nums = [1,2,1,2], limit = 2
**Output:** 0
**Explanation:** nums is already complementary.
```

**Constraints:**

* `n == nums.length`
* `2 <= n <= 105`
* `1 <= nums[i] <= limit <= 105`
* `n` is even.

## ac

```java
```
