--update: remove from beginning

Author: ashokdey

src/_DataStructures_/LinkedList/LinkedList.test.js

@@ -47,6 +47,7 @@ describe('Data Structures: Linked Lists', () => {
       list.addAtEnd(15);
       expect(list.head.data).toEqual(12);
       expect(list.head.next.data).toEqual(15);
+      expect(list.length()).toEqual(2);
     });
 
     it('Should return the present size of the list using list.length()', () => {
@@ -56,5 +57,15 @@ describe('Data Structures: Linked Lists', () => {
       list.addAtBeginning(3);
       expect(list.length()).toEqual(3);
     });
+
+    it('Should remove element at front using list.removeFromBeginning()', () => {
+      list.addAtBeginning(12);
+      expect(list.removeFromBeginning()).toEqual(12);
+
+      list.addAtBeginning(15);
+      list.addAtBeginning(16);
+      expect(list.removeFromBeginning()).toEqual(16);
+      expect(list.length()).toEqual(1);
+    });
   });
 });

src/_DataStructures_/LinkedList/index.js

@@ -46,6 +46,15 @@ class LinkedList {
     }
     return count;
   }
+
+  removeFromBeginning() {
+    if (!this.head) {
+      return null;
+    }
+    const temp = this.head;
+    this.head = this.head.next;
+    return temp.data;
+  }
 }
 
 module.exports = { LinkedList, Node };