Problem Description
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.
Key Insights
- The output array should be exactly double the size of the input array, containing two copies of the input array.
- The indices of the output array can be split into two segments: the first segment (0 to n-1) mirrors the input array, and the second segment (n to 2n-1) is identical to the first segment.
- The problem requires simple array manipulation and is straightforward in terms of implementation.
Space and Time Complexity
Time Complexity: O(n)
Space Complexity: O(n)
Solution
To solve this problem, we can use a simple array concatenation approach. We will create a new array of size 2n and fill it with the elements of the input array nums. The first half of the new array will be filled with the elements of nums, and the second half will be a duplicate of the first half. This can be achieved using a loop that iterates through the input array.