Real one-line solution
Intuition\nWe want to obtain the concatenation of an array with itself.\n\n# Approach\nWe can get the concatenation of the array by appending a copy of the same
# Intuition\nWe want to obtain the concatenation of an array with itself.\n\n# Approach\nWe can get the concatenation of the array by appending a copy of the same array to the end.\n\n# Complexity\n- Time complexity:\nO(n)\n\n- Space complexity:\nO(n)\n\n# Code\n```\n/**\n * @param {number[]} nums\n * @return {number[]}\n */\nconst getConcatenation = nums => nums.concat(nums);\n```
['JavaScript']