linkedlist add last

Author: amejiarosario

lib/data-structures/linked-lists/linked-list.js

@@ -0,0 +1,23 @@
+const Node = require('./node');
+
+class LinkedList {
+  constructor() {
+    this.root = null;
+  }
+
+  addLast(value) {
+    const node = new Node(value);
+
+    if(this.root) {
+      let currentNode = this.root;
+      while(currentNode && currentNode.next) {
+        currentNode = currentNode.next;
+      }
+      currentNode.next = node;
+    } else {
+      this.root = node;
+    }
+  }
+}
+
+module.exports = LinkedList;

lib/data-structures/linked-lists/linked-list.spec.js

@@ -0,0 +1,24 @@
+const LinkedList = require('./linked-list');
+
+describe('LinkedList', function () {
+  let linkedList;
+
+  beforeEach(() => {
+    linkedList = new LinkedList();
+  });
+
+  describe('#addLast', () => {
+    it('should add element to end', () => {
+      linkedList.addLast('a');
+      expect(linkedList.root.value).toBe('a');
+    });
+
+    it('should link values', () => {
+      linkedList.addLast('a');
+      linkedList.addLast('b');
+
+      expect(linkedList.root.value).toBe('a');
+      expect(linkedList.root.next.value).toBe('b');
+    });
+  });
+});

lib/data-structures/linked-lists/node.js

@@ -0,0 +1,8 @@
+class Node {
+  constructor(value) {
+    this.value = value;
+    this.next = null;
+  }
+}
+
+module.exports = Node;

lib/data-structures/queues/queue.spec.js

@@ -1,4 +1,4 @@
-const Queue = require('./queue-1.js');
+const Queue = require('./queue.js');
 
 describe('Queue', function () {
   let queue;