Explain sets data structure.

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Accepted Answer

A set is a collection of items that are **unique** Sets in ES6 are **ordered**: elements of the set can be iterated in the insertion order. The set can store **any type of value** whether primitive or objects. // Creates an empty Set.
const mySet = new Set();

// Creates a Set with {1, 2, 3, 4}
const numbers = new Set([1, 2, 3, 3, 4]);

Add to the Set.
mySet.add(5);
mySet.add("hello"); // Adds the string "hello".

// Check if a value exists in the set
mySet.has(5);     // Returns true
mySet.has("world"); // Returns false

// size of a set
console.log(uniqueNumbers.size);  // 3

// delete a value from the set
mySet.delete(5); // Removes 5 from the Set.

// Removes all elements from the Set.
mySet.clear();

// iteration over the elements of a set
for (let value of mySet) {
  console.log(value); // Prints each value in the Set.
}

mySet.forEach(value => {
  console.log(value); // Prints each value in the Set.
});

// create array from set
const arrayFromSet = [...uniqueNumbers];
const arrayFromSet = Array.from(uniqueNumbers);

const setA = new Set([1, 2, 3]);
const setB = new Set([3, 4, 5]);

// union of a two sets
const unionSet = new Set([...setA, ...setB]); // [1, 2, 3, 4, 5]

//intersection of two sets
const intersectionSet = new Set([...setA].filter(x => setB.has(x))); // [3]

//difference of two sets
const differenceSet = new Set([...setA].filter(x => !setB.has(x))); // [1, 2]

Explain sets data structure.

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