Easy Solution
Dart []\nclass Solution {\n  List<int> getConcatenation(List<int> nums) {\n    List<int> output =[];\n    for(int i=0;i<nums.length;i++) {\n        output.add(n
```Dart []\nclass Solution {\n  List<int> getConcatenation(List<int> nums) {\n    List<int> output =[];\n    for(int i=0;i<nums.length;i++) {\n        output.add(nums[i]);\n    } for(int i=0;i<nums.length;i++) {\n        output.add(nums[i]);\n    } return output;\n  }\n}\n```\n```Java []\nclass Solution {\n    public int[] getConcatenation(int[] nums) {\n        int[] output = new int[nums.length*2];\n        for(int i=0;i<nums.length;i++) {\n            output[i]=nums[i];\n        } for(int i=0;i<nums.length;i++) {\n             output[nums.length+i]=nums[i];\n        } return output;\n    }\n}\n```\n```Python []\nclass Solution(object):\n    def getConcatenation(self, nums):\n        """\n        :type nums: List[int]\n        :rtype: List[int]\n        """\n        return nums + nums\n        \n```\n```Python3 []\nclass Solution:\n    def getConcatenation(self, nums: List[int]) -> List[int]:\n        nums+=nums\n        return nums\n```\n```C++ []\nclass Solution {\npublic:\n    vector<int> getConcatenation(vector<int>& nums) {\n         vector<int> output = {};\n        for(int i=0;i<nums.size();i++) {\n            output.push_back(nums[i]);\n        } for(int i=0;i<nums.size();i++) {\n            output.push_back(nums[i]);\n        } return output;\n    }\n};\n```\n
['Array', 'Python', 'C++', 'Java', 'Python3', 'Dart']