Tell us what’s happening:
My code isn’t passing the test cases, even though I am taking care of cases where the head or tail is removed.
Your code so far
var Node = function(data, prev) {
this.data = data;
this.prev = prev;
this.next = null;
};
var DoublyLinkedList = function() {
this.head = null;
this.tail = null;
// change code below this line
this.add = function(element) {
var node = new Node(element, null);
if (this.head === null) this.head = node;
if (this.tail === null) {
this.tail = this.head;
while (this.tail.next !== null) this.tail = this.tail.next;
}
else {
var ptr = this.head;
while (ptr !== this.tail && this.tail !== null) ptr = ptr.next;
this.tail.next = node;
node.prev = this.tail;
this.tail = node;
}
}
this.remove = function(element) {
var ptr = this.head;
if (this.head === null) return null;
if (this.head.element === element) {
this.head = this.head.next;
this.head.prev = null;
}
if (this.tail.element === element) {
this.tail = this.tail.prev;
this.tail.next = null;
}
while (ptr !== null) {
if (ptr.element === element) {
ptr.prev.next = ptr.next;
ptr.next.prev = ptr.prev;
}
ptr = ptr.next;
}
}
// change code above this line
};
Your browser information:
User Agent is: Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.121 Safari/537.36.
Link to the challenge:
https://learn.freecodecamp.org/coding-interview-prep/data-structures/create-a-doubly-linked-list/
