C# The best solution to the problem C#
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity: O(n)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: O(2n)\n![lo5ad7qsga531.jpg](https://assets.leetcode.com/users/images/a351c520-4757-47cb-80c9-d9767daa80d5_1707145634.9566977.jpeg)\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\npublic class Solution\n{\n    public int[] GetConcatenation(int[] nums)\n    {\n        // nums => n Length\n        // Answer => 1n Length\n        // Answer[i] == nums[i]\n        // Answer[i + n] == nums[i]\n        // 0 <= i < n\n\n        int n = nums.Length;\n        int[] Answer = new int[n * 2];\n\n        for (int i = 0; i < n; i++)\n        {\n            Answer[i] = Answer[n + i] = nums[i];\n        }\n        return Answer;\n    }\n}\n```
['C#']