update: table of contents in README

Author: ashokdey

README.md

@@ -3,4 +3,21 @@
 [![Build Status](https://travis-ci.org/knaxus/problem-solving-javascript.svg?branch=master)](https://travis-ci.org/knaxus/problem-solving-javascript)
 [![Coverage Status](https://coveralls.io/repos/github/knaxus/problem-solving-javascript/badge.svg?branch=master)](https://coveralls.io/github/knaxus/problem-solving-javascript?branch=master)
 
-Collection of interview questions with Unit Tests
+Collection of interview questions with Unit Tests. Problems includes Data Structures, Logical and few Classical problems.
+
+## Table of Contents
+
+### Classics
+
+- [Caeser Cipher](src/_Classics_/caeser_cipher)
+- [Fibonacci](src/_Classics_/fibonacci)
+
+### Data Structures
+
+- [Singly Linked List](src/_DataStructures_/LinkedList)
+  - [N Element From Last](src/_DataStructures_/LinkedList/element-from-last)
+  - [Middle Node](src/_DataStructures_/LinkedList/middle-node)
+- [Stack](src/_DataStructures_/Stack)
+  - [Implement Queue Using Stack](src/_DataStructures_/Stack/immitate-queue-using-stack)
+- [Queue](src/_DataStructures_/Queue)
+  - [Weave](src/_DataStructures_/Queue/weave)