Strong reference cycles

A strong reference cycle, or strong retain cycle, is where the instances of two classes hold a strong reference to each other, preventing ARC from releasing either instance. Once again, we are not able to use a playground for this example, so we need to create an Xcode project. In this project, we start off by creating two classes named MyClass1_Strong and MyClass2_Strong with the following code:

class MyClass1_Strong { 
    var name = ""
    var class2: MyClass2_Strong? 
    init(name: String) {
        self.name = name
        print("Initializing class1_Strong with name \(self.name)")
    }
    deinit {
        print("Releasing class1_Strong with name \(self.name)")
    }
}
class MyClass2_Strong { 
    var name = ""
    var class1: MyClass1_Strong? 
    init(name: String) {
        self.name = name
        print("Initializing class1_Strong with name \(self.name)")
    }
    deinit {
        print(&quot...