What difficulties might we face when sorting data in an array?

• Unstable sorting (elements with equal value may change their relative order).
• Inefficiency for large data volumes (high time or space complexity).
• Sensitivity to data type (necessity to implement a comparator for custom types).
• Performance issues when sorting arrays of reference types due to overhead of copying or comparing objects.
• Memory consumption when using certain algorithms (e.g., Heapsort, Mergesort).
• Complexity of implementing multi-criteria sorting.
• Impact on UI responsiveness when executed on the main thread.
• Need to ensure thread safety when sorting arrays accessible from different threads.

Example in Swift:

// Sorting an array of custom objects without implementing Comparable
struct Person {
    let name: String
    let age: Int
}

let people = [Person(name: "Alice", age: 30), Person(name: "Bob", age: 25), Person(name: "Charlie", age: 30)]

// This will cause a compilation error because Person does not conform to Comparable
// let sortedPeople = people.sorted()

// Sorting using a comparator closure
let sortedPeople = people.sorted { $0.age < $1.age }
// Result: [Person(name: "Bob", age: 25), Person(name: "Alice", age: 30), Person(name: "Charlie", age: 30)]
// Note the possible instability: the order of Alice and Charlie may change