Sets and tuples solve different jobs

A club register should avoid duplicate member names, while a quick calculation may return both a total and a count. A Set stores unique elements without a promised order. A tuple groups a fixed collection of values that can have different types and optional field labels.

Sets support union, intersection and subtraction for membership questions. Their elements must be Hashable. A tuple’s shape is fixed by its type; it is not a growable list. Labels such as total and count clarify what its fields mean without defining a full custom structure.

Save this complete program as main.swift and run it with the Swift toolchain. No separate input file is needed.

Swift · complete program

let art: Set<String> = ["Diya", "Saira", "Diya"]
let music: Set<String> = ["Saira", "Noor"]
print(art.intersection(music).sorted())
let report = (total: 160, count: 2)
print(report.total / report.count)

Expected output

["Saira"]
80

Follow the execution

The duplicate Diya does not create a second set element. The intersection contains Saira, and sorting gives deterministic output. The tuple carries two integers, so dividing its named fields returns the integer average 80.

Try this program in the Swift compiler. Paste the complete source above.

Your task: Which collection should preserve duplicate attendance entries in their original order?

Swift · complete program

let art: Set<String> = ["Diya", "Saira", "Diya"]
let music: Set<String> = ["Saira", "Noor"]
print(art.intersection(music).sorted())
let report = (total: 160, count: 2)
print(report.total / report.count)

Worked answer

An array should. A set would discard duplicates and would not promise the original order, changing the meaning of the attendance record.

A large tuple can become hard to understand; a named struct is often clearer for a domain model. Set membership describes equality under its element type, not proof that two equal names represent the same person.

An array should. A set would discard duplicates and would not promise the original order, changing the meaning of the attendance record. A large tuple can become hard to understand; a named struct is often clearer for a domain model.

Further reading: official Swift language guide.