What is the Time Complexity of creating set from array?

Question

I want to find time complexity of following code. I have an array of integer having duplicate values. I created set from array to remove duplicate entries and then initialize new array from that set using spread operator.

Code:

let list=[1,1,2,3,4,4]
let uniqueNumbers=[...new Set(list)]
console.log(uniqueNumbers)

Answer 1

There are 2 things being done here:

• new Set(list) iterates over every element of the list and puts it into a Set. This is O(n)
• [...set] iterates over every element of the Set and puts it into an array. This will also be O(n) in nearly all cases.

Both operations are O(n), so overall, the computational complexity is O(n).