###### tags: `Array`

# LeetCode 1929.Concatenation of Array

Given an integer array ```nums``` of length ```n```, you want to create an array ```ans``` of length ```2n``` where ```ans[i] == nums[i]``` and ```ans[i + n] == nums[i]``` for ```0 <= i < n``` (0-indexed).

Specifically, ```ans``` is the concatenation of two ```nums``` arrays.

Return the array ```ans```.

>Example 1:

Input: nums = [1,2,1]
Output: [1,2,1,1,2,1]
Explanation: The array ans is formed as follows:
- ans = [nums[0],nums[1],nums[2],nums[0],nums[1],nums[2]]
- ans = [1,2,1,1,2,1]

>Example 2:

Input: nums = [1,3,2,1]
Output: [1,3,2,1,1,3,2,1]
Explanation: The array ans is formed as follows:
- ans = [nums[0],nums[1],nums[2],nums[3],nums[0],nums[1],nums[2],nums[3]]
- ans = [1,3,2,1,1,3,2,1]

### Constraints:

- $n == nums.length$
- $1 <= n <= 1000$
- $1 <= nums[i] <= 1000$
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### Idea:
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### Solution:

Python:

class Solution:
    def getConcatenation(self, nums: List[int]) -> List[int]:
        return nums + nums

C++: