# Initial filling of Sets in JavaScript

It is possible to fill a `Set` collection with some values during creation by passing an array with data as a parameter:

`let set = new Set([1, 2, 3]);`

Moreover, if there are duplicates in the array, then they will not appear in the collection:

`let set = new Set([1, 2, 3, 3, 4, 4, 5]); console.log(set); // shows [1, 2, 3, 4, 5]`

Given an array of numbers:

`let arr = [1, 2, 3, 1, 3, 4];`

Using this array create a `Set` collection.

Create a `Set` collection with initial values `1`, `2` and `3`. Use the `add` method to add another number `2` to the collection. Output the contents of the collection to the console, make sure that the number `2` has not been added repeatedly.

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