update: entry in readme

Author: ashokdey

README.md

@@ -14,15 +14,19 @@ Collection of interview questions with Unit Tests. Problems includes Data Struct
 ### 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)
   - [Detect Loop](src/_DataStructures_/LinkedList/loop-in-list)
   - [Reverse Linked List](src/_DataStructures_/LinkedList/reverse-linked-list)
+
 - [Stack](src/_DataStructures_/Stack)
+
   - [Implement Queue Using Stack](src/_DataStructures_/Stack/immitate-queue-using-stack)
   - [Baseball Game](src/_DataStructures_/Stack/baseball-game)
   - [Minimum Stack](src/_DataStructures_/Stack/min-stack)
   - [Balanced Parenthesis](src/_DataStructures_/Stack/balanced-parenthesis)
+  - [Implement 2 Stacks using Single Array](src/_DataStructures_/Stack/2-stacks-using1-array)
 
 - [Queue](src/_DataStructures_/Queue)
   - [Weave](src/_DataStructures_/Queue/weave)
@@ -65,9 +69,10 @@ Collection of interview questions with Unit Tests. Problems includes Data Struct
 
 ## CONTRIBUTION Guide
 
-It's great to know that you want to contribute to this repo. Thanks for taking interest. Before you start, read the following carefully. 
+It's great to know that you want to contribute to this repo. Thanks for taking interest. Before you start, read the following carefully.
 
 - When adding a new **problem** with solution
+
   - Take care of the filename convention (Very Important)
   - Problem statement should be there with examples
   - Make sure you add the Run Time complexity of your solution
@@ -76,7 +81,8 @@ It's great to know that you want to contribute to this repo. Thanks for taking i
   - Strictly follow ESLINT rules
 
 - When adding a Unit Test
+
   - Take care of the file name convention
   - Make sure CI (Travis) is passing
-  
-Keep an eye on this guide, it's subjected to change frequently. 
+
+Keep an eye on this guide, it's subjected to change frequently.