Sets in Swift

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by The Captain

August 1, 2023

Working with Sets in Swift

A set is an unordered collection of unique values in Swift. It is implemented as a hash table where values are hashed to determine their positions within the collection.

Creating a set:

let fruits: Set = ["Apple", "Banana", "Orange"]

Accessing and modifying a set:

if fruits.contains("Apple") { fruits.remove("Apple") } fruits.insert("Mango")

Iterating over a set:

for fruit in fruits { print(fruit) }

Performing set operations:

let moreFruits: Set = ["Pear", "Kiwi"] let allFruits = fruits.union(moreFruits) let commonFruits = fruits.intersection(moreFruits) let differentFruits = fruits.symmetricDifference(moreFruits) let fruitsWithoutCommon = fruits.subtracting(moreFruits)

Set operations allow you to combine, find common elements, find exclusive elements, or subtract elements from two sets.

Set membership and equality:

let setA: Set = [1, 2, 3] let setB: Set = [3, 4, 5] if setA.isSubset(of: setB) { print("setA is a subset of setB") } if setB.isSuperset(of: setA) { print("setB is a superset of setA") } if setA.isDisjoint(with: setB) { print("setA and setB have no common elements") } let setC: Set = [3, 4] if setA == setC { print("setA and setC have the same elements") }

Set membership can be checked using the `isSubset(of:)` and `isSuperset(of:)` methods. The `isDisjoint(with:)` method checks if two sets have any common elements. Set equality can be checked using the `==` operator.

Summary: Sets in Swift are unordered collections of unique values. They can be created, modified, and accessed using various methods and operators. Set operations and membership checks make working with sets efficient and convenient.