Practice 50 Swift Memory Management Programming Questions

Practice 50 Swift Memory Management Programming Questions

Q1. Write a Swift program to demonstrate the use of automatic reference counting (ARC) by creating a class with a property and showing the memory management behavior.  
Input:  
Property = "Hello World"  
Expected Output:  
ARC is managing the memory.

Q2. Write a Swift program to create a class Person and demonstrate the effect of strong references by creating an instance and showing memory behavior.  
Input:  
name = "John Doe"  
Expected Output:  
Strong reference causes memory to persist until explicitly deallocated.

Q3. Write a Swift program to create a class Book with a method deinit() to show how deinitializers are used to release resources when an object is deallocated.  
Input:  
Book = "Swift Programming"  
Expected Output:  
Book instance deallocated.

Q4. Write a Swift program to demonstrate the concept of weak references by creating a class with weak properties and observing the memory management behavior.  
Input:  
person = Person(name: "Alice")  
Expected Output:  
Weak reference does not increase the reference count.

Q5. Write a Swift program to demonstrate the use of unowned references by creating a strong reference cycle and using unowned to break the cycle.  
Input:  
person = Person(name: "Bob")  
Expected Output:  
Unowned reference prevents strong reference cycle.

Q6. Write a Swift program to create a class Car with a deinitializer that releases resources when the object is deallocated.  
Input:  
car = "BMW"  
Expected Output:  
Car object deallocated.

Q7. Write a Swift program to show how retain cycles occur by creating a scenario where two objects retain each other.  
Input:  
person = Person(name: "Charlie")  
Expected Output:  
Retain cycle occurs and objects are not deallocated.

Q8. Write a Swift program to demonstrate how to resolve retain cycles using weak references.  
Input:  
parent = Parent(name: "Daniel")  
Expected Output:  
Retain cycle resolved with weak reference.

Q9. Write a Swift program to demonstrate the deinit method by creating a class and observing when it is called during the deallocation of an object.  
Input:  
object = "Example"  
Expected Output:  
deinit method is called for Example.

Q10. Write a Swift program to create a Student class with a method deinit() that prints a message when the object is deallocated.  
Input:  
student = "Mark"  
Expected Output:  
Student object Mark is deallocated.

Q11. Write a Swift program to demonstrate the effect of strong and weak references in a closure.  
Input:  
closure = { print("Hello") }  
Expected Output:  
Strong reference inside closure causes memory retention.

Q12. Write a Swift program to create a class Library with a weak reference to Book, and demonstrate memory management when the Book object is deallocated.  
Input:  
library = Library(), book = Book(title: "iOS Programming")  
Expected Output:  
Book instance is deallocated when no longer referenced by any strong references.

Q13. Write a Swift program to demonstrate how to use weak references to prevent memory leaks in a parent-child relationship.  
Input:  
parent = Parent(), child = Child()  
Expected Output:  
Memory leak prevented using weak reference.

Q14. Write a Swift program to demonstrate how unowned references prevent memory leaks in a closure capturing a reference to an object.  
Input:  
closure = { [unowned self] in self.doSomething() }  
Expected Output:  
Unowned reference prevents strong reference cycle in closure.

Q15. Write a Swift program to show how ARC manages memory by showing the reference count of an object before and after strong, weak, and unowned references are set.  
Input:  
object = SomeObject()  
Expected Output:  
Reference count before weak reference: 1
Reference count after weak reference: 0

Q16. Write a Swift program to create a class with multiple strong references and observe how memory is managed when one reference goes out of scope.  
Input:  
object = SomeClass()  
Expected Output:  
Object memory is released when the last strong reference is deallocated.

Q17. Write a Swift program to demonstrate how circular references can be avoided in closures.  
Input:  
closure = { [weak self] in self?.performAction() }  
Expected Output:  
No memory leak due to weak self in closure.

Q18. Write a Swift program to create a class User with a method logout() that is called when an object is deallocated.  
Input:  
user = "John"  
Expected Output:  
User John has logged out and the object is deallocated.

Q19. Write a Swift program to show how memory is managed with closures capturing reference types and value types differently.  
Input:  
closure = { [weak self] in self?.updateUI() }  
Expected Output:  
Captured reference to value type doesn’t cause retain cycle.

Q20. Write a Swift program to demonstrate the use of deinit with a class and how ARC cleans up memory when the object goes out of scope.  
Input:  
object = "Resource"  
Expected Output:  
deinit method is called and resources are cleaned up.

Q21. Write a Swift program to show how unowned references are used in closures to prevent memory leaks.  
Input:  
closure = { [unowned self] in self.doWork() }  
Expected Output:  
No memory leak due to unowned reference in closure.

Q22. Write a Swift program to demonstrate how objects with strong references are deallocated when they go out of scope.  
Input:  
object = "ObjectName"  
Expected Output:  
ObjectName is deallocated when it goes out of scope.

Q23. Write a Swift program to create a class Employee and show how to properly use weak references to prevent strong reference cycles in the class.  
Input:  
employee = Employee(name: "Alice")  
Expected Output:  
Memory leak prevented using weak reference.

Q24. Write a Swift program to demonstrate the difference between strong and weak references in ARC.  
Input:  
strongRef = object, weakRef = object  
Expected Output:  
Strong reference retains memory, weak reference does not.

Q25. Write a Swift program to create a class Person and demonstrate how to properly manage the deallocation using deinit method.  
Input:  
person = "David"  
Expected Output:  
David is deallocated successfully.

Q26. Write a Swift program to show how memory is freed automatically when the object goes out of scope, using the deinit method.  
Input:  
object = "SomeObject"  
Expected Output:  
Memory is freed when object goes out of scope.

Q27. Write a Swift program to demonstrate the use of weak references when capturing self in closures.  
Input:  
closure = { [weak self] in self?.executeTask() }  
Expected Output:  
No retain cycle due to weak self in closure.

Q28. Write a Swift program to create a class Task with a method deinit() that shows the release of resources when the object is deallocated.  
Input:  
task = Task()  
Expected Output:  
Task instance deallocated and resources freed.

Q29. Write a Swift program to demonstrate the memory management behavior when using reference types in closures.  
Input:  
closure = { obj in obj?.performAction() }  
Expected Output:  
Reference type object is captured and retained by closure.

Q30. Write a Swift program to demonstrate the behavior of ARC with strong references in a cyclic dependency between two classes.  
Input:  
classA = ClassA(), classB = ClassB()  
Expected Output:  
Memory leak occurs due to cyclic reference.

Q31. Write a Swift program to create a class with a strong reference cycle and show how ARC handles memory management.  
Input:  
personA = PersonA(), personB = PersonB()  
Expected Output:  
Strong reference cycle detected and memory is not released.

Q32. Write a Swift program to create a class with a deinit method and show when memory is deallocated.  
Input:  
instance = "MyObject"  
Expected Output:  
Memory deallocated and deinit method called.

Q33. Write a Swift program to demonstrate how weak references prevent retain cycles in a parent-child relationship.  
Input:  
parent = Parent(), child = Child()  
Expected Output:  
Weak reference prevents retain cycle between parent and child.

Q34. Write a Swift program to create a class with a strong reference and weak reference, and print the reference count before and after deallocation.  
Input:  
object = SomeObject()  
Expected Output:  
Reference count before deallocation: 1
Reference count after deallocation: 0

Q35. Write a Swift program to demonstrate the use of ARC in a scenario where objects are deallocated after losing all strong references.  
Input:  
object = "SomeClass"  
Expected Output:  
Object is deallocated when no strong references exist.

Q36. Write a Swift program to show how to fix a retain cycle in closures by using weak or unowned references.  
Input:  
closure = { [weak self] in self?.method() }  
Expected Output:  
Retain cycle fixed with weak reference.

Q37. Write a Swift program to create an object that automatically deallocates when the reference count drops to zero.  
Input:  
object = "AutoDeallocate"  
Expected Output:  
Object is deallocated when reference count is zero.

Q38. Write a Swift program to create a TaskManager class with a deinit() method that prints when the task manager is deallocated.  
Input:  
taskManager = TaskManager()  
Expected Output:  
TaskManager is deallocated.

Q39. Write a Swift program to create a class with a strong reference and simulate memory deallocation with weak references.  
Input:  
object = "TestObject"  
Expected Output:  
Memory is deallocated using weak reference.

Q40. Write a Swift program to show how weak references allow deallocation when no longer needed.  
Input:  
object = "ExampleObject"  
Expected Output:  
ExampleObject is deallocated using weak reference.

Q41. Write a Swift program to create an instance with strong and weak references, and show when each reference is deallocated.  
Input:  
strong = StrongObject(), weak = WeakObject()  
Expected Output:  
Strong reference retains, weak reference allows deallocation.

Q42. Write a Swift program to create a class with an unowned reference and demonstrate memory behavior when the object goes out of scope.  
Input:  
object = UnownedObject()  
Expected Output:  
Unowned reference prevents memory leak.

Q43. Write a Swift program to demonstrate the difference between weak and unowned references.  
Input:  
weakRef = SomeObject(), unownedRef = SomeObject()  
Expected Output:  
Weak reference can be nil, unowned cannot be nil.

Q44. Write a Swift program to demonstrate how to manage memory with ARC in a multi-threaded environment.  
Input:  
object = "MultiThreadedObject"  
Expected Output:  
Memory management handled by ARC across threads.

Q45. Write a Swift program to show how to prevent memory leaks by using weak references in a collection of objects.  
Input:  
collection = [SomeObject(), AnotherObject()]  
Expected Output:  
Memory leaks prevented by weak references in collection.

Q46. Write a Swift program to create a class that tracks reference counts and shows the current count before and after strong, weak, and unowned references are set.  
Input:  
object = "ReferenceObject"  
Expected Output:  
Reference count before weak reference: 1
Reference count after weak reference: 0

Q47. Write a Swift program to show that weak references do not retain objects in closures.  
Input:  
closure = { [weak self] in self?.doSomething() }  
Expected Output:  
Weak reference does not retain object inside closure.

Q48. Write a Swift program to demonstrate a retain cycle scenario with strong references and how weak references resolve it.  
Input:  
classA = ClassA(), classB = ClassB()  
Expected Output:  
Memory leak prevented by weak reference.

Q49. Write a Swift program to show how ARC works with strong, weak, and unowned references in a class with circular dependencies.  
Input:  
classA = ClassA(), classB = ClassB()  
Expected Output:  
Retain cycle avoided by weak reference.

Q50. Write a Swift program to demonstrate how weak and unowned references allow for proper memory deallocation in a strongly referenced cycle.  
Input:  
classA = ClassA(), classB = ClassB()  
Expected Output:  
Memory properly deallocated using weak or unowned references.