2 lines C++
\nclass Solution {\npublic:\n    vector<int> getConcatenation(vector<int>& nums) {\n        nums.insert(nums.end(), nums.begin(), nums.end());\n        return n
```\nclass Solution {\npublic:\n    vector<int> getConcatenation(vector<int>& nums) {\n        nums.insert(nums.end(), nums.begin(), nums.end());\n        return nums;\n    }\n};\n```
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