💡 Intuition

• The idea is to create an array of length 2n and update the values at indices i and i + n with num[i] while iterating through the existing array.

🚀 Solution

func getConcatenation(nums []int) []int {
	var result = make([]int,2*len(nums))

	for index,num := range nums {
		result[index] = num;
		result[index+len(nums)] = num;
	}

	return result;
}

⏳ Time Complexity

• Since we are taking single loop for the array of length n, the time complexity will be O(n)