Adding items to end of linked list

Question

I\'m studying for an exam, and this is a problem from an old test:

We have a singly linked list with a list head with the following declaration:

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Answer 1

If you keep track of the tail node, you don't need to loop through every element in the list.

Just update the tail to point to the new node:

AddValueToListEnd(value) {
    var node = new Node(value);

    if(!this.head) {
        this.head = node;
        this.tail = node;
    } else {
        this.tail.next = node; //point old tail to new node
    }
        
    this.tail = node; //now set the new node as the new tail
}

In plain English:

• Create a new node with the given value
• If the list is empty, point head and tail to the new node
• If the list is not empty, set the old tail.next to be the new node
• In either case, update the tail pointer to be the new node