How can cyclic references in memory management be eliminated to prevent leaks?

Cyclic references occur when two or more objects reference each other, which prevents automatic memory deallocation, especially when using reference counting.

In iOS (Objective-C/Swift), to prevent leaks caused by cyclic references, the following are used:

• Weak references (weak) — do not increase the reference count, automatically set to nil when the object is deallocated.
• Unowned references (unowned) — do not increase the reference count, but are not set to nil, used when the object is guaranteed to exist.

For example, in Swift:

class A {
    var b: B?
}

class B {
    weak var a: A?  // weak reference to avoid cycle
}

Using weak or unowned breaks the cycle, allowing ARC to correctly deallocate objects and prevent memory leaks.