How can two generic linked list in swift can be compared?

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I have a generic linked list and I can check if two linked list are equal if each of the node value are same and are in order. I have a function which divides linked list in two part and later I want to check two list has same value in it's node.

func divideList(atIndex index:Int) -> (first: LLGeneric<T>?,second: LLGeneric<T>?)

I looking it for my use case where I can check palindrome in linked list after dividing and then comparing ( after reversing one list).

Note: my linked list node is generic something like 

   class LLGenericNode<T> {
    var value: T
    var next: LLGenericNode?
    weak var previous: LLGenericNode?
    init(_ value: T) {
        self.value = value
    }
}
swift iequatable generics
2 Answers

One-liner solution: It should be enough to define a generic T: Equatable, making sure on overloading the == operator, you compare the current values and the next nodes.

Note that with lhs.next == rhs.next you'll cover both recursion and nullability in one shot:

class Node <T: Equatable>: Equatable {
    static func == (lhs: Node, rhs: Node) -> Bool {
        lhs.value == rhs.value && lhs.next == rhs.next
    }
}
user_24507550
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