# LeetCode 1470. Shuffle the Array

## Description

https://leetcode.com/problems/shuffle-the-array/

Given the array `nums` consisting of `2n` elements in the form `[x1,x2,...,xn,y1,y2,...,yn]`.

Return the array in the form `[x1,y1,x2,y2,...,xn,yn]`.

Example 1:

```Input: nums = [2,5,1,3,4,7], n = 3
Output: [2,3,5,4,1,7]
Explanation: Since x1=2, x2=5, x3=1, y1=3, y2=4, y3=7 then the answer is [2,3,5,4,1,7].
```

Example 2:

```Input: nums = [1,2,3,4,4,3,2,1], n = 4
Output: [1,4,2,3,3,2,4,1]
```

Example 3:

```Input: nums = [1,1,2,2], n = 2
Output: [1,2,1,2]
```

Constraints:

• `1 <= n <= 500`
• `nums.length == 2n`
• `1 <= nums[i] <= 10^3`

## Explanation

Two pointers, one from the beginning of the list, the other one from the n th position of the list.

## Python Solution

``````class Solution:
def shuffle(self, nums: List[int], n: int) -> List[int]:
results = []

j = n
for i in range(0, n):
results.append(nums[i])
results.append(nums[j])
j += 1

return results``````
• Time complexity: O(N).
• Space complexity: O(N).