Array.swift

import Foundation


class MyView: CustomStringConvertible { 
    let index: UInt
    var ID: String
    
    init(withIndex index: UInt) {
        self.index = index
        ID = String(index)
    }
    
    var description: String {
        return "(\(index), \(ID))"
    }
}

class MyViewController {
    var strings: [String] = []
    var views: [MyView] = []
}

class FirstViewController: MyViewController { }
class SecondViewController: MyViewController { }

// 
var firstVC = FirstViewController()
firstVC.strings = ["One", "Two", "Three"]
firstVC.views = [MyView(withIndex: 1), MyView(withIndex: 2), MyView(withIndex: 3)]

let secondVC = SecondViewController()
secondVC.strings = firstVC.strings
secondVC.views = firstVC.views

secondVC.strings.popLast()
print(firstVC.strings)

secondVC.views.popLast()
print(firstVC.views)

secondVC.views.last?.ID = "4"
print(firstVC.views)

/*
Question: what will be printed in console?
*/