64 lines
1.3 KiB
JavaScript
64 lines
1.3 KiB
JavaScript
// https://www.freecodecamp.org/learn/coding-interview-prep/data-structures/add-elements-at-a-specific-index-in-a-linked-list
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function LinkedList() {
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var length = 0;
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var head = null;
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var Node = function (element) {
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this.element = element;
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this.next = null;
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};
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this.size = function () {
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return length;
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};
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this.head = function () {
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return head;
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};
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this.add = function (element) {
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var node = new Node(element);
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if (head === null) {
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head = node;
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} else {
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var currentNode = head;
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while (currentNode.next) {
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currentNode = currentNode.next;
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}
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currentNode.next = node;
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}
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length++;
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};
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// Only change code below this line
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this.addAt = (index, element) => {
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if (index < 0 || index > length) {
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return false;
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}
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let i = 0;
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let previousNode = null;
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let nextNode = head;
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while (i < index && nextNode !== null) {
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i++;
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previousNode = nextNode;
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nextNode = nextNode.next;
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}
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if (i != index) {
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return false;
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}
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const node = new Node(element);
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if (previousNode === null) {
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head = node;
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} else {
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previousNode.next = node;
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}
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node.next = nextNode;
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length++;
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return true;
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};
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// Only change code above this line
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}
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