Java 4 lines
\npublic int[] getConcatenation(int[] nums) {\n\tint[] result = new int[nums.length * 2];\n\tfor(int i=0;i<nums.length;i++)\n\t\tresult[i + nums.length] = resul
```\npublic int[] getConcatenation(int[] nums) {\n\tint[] result = new int[nums.length * 2];\n\tfor(int i=0;i<nums.length;i++)\n\t\tresult[i + nums.length] = result[i] = nums[i];\n\treturn result;\n}\n```
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