Easy for beginners python and JS Solution
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(n)\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Js Code\n```\n/**\n * @param {number[]} nums\n * @return {number[]}\n */\nvar getConcatenation = function(nums) {\n    let arr = []\n    for(let i=0; i < nums.length; i++) {\n        arr.push(nums[i])\n    }\n    for(let j=0; j < nums.length; j++) {\n        arr.push(nums[j])\n    }\n    return arr\n};\n```\n# Python Code\n```\nclass Solution:\n    def getConcatenation(self, nums: List[int]) -> List[int]:\n        arr = []\n        for i in range(len(nums)):\n            arr.append(nums[i])\n        for j in range(len(nums)):\n            arr.append(nums[j])\n        return arr\n```
['Python3', 'JavaScript']