updating gitignore file

Author: rohan-paul

.gitignore

@@ -51,4 +51,13 @@ random-code-1.js
 random-code-2.js
 random-code-3.js
 random-code-4.js
-performance-1.js
+performance-1.js
+
+
+#ignore file name ending in "-bkp.js" OR "-bkp.ts"  OR "-bkp.py"  OR "-test.js" OR "-test.ts" OR "-test.py" in its name. So I will have to put "-test.js" at all files that is just for my development-time random testing code .
+**/*-bkp.js
+**/*-bkp.ts
+**/*-bkp.py
+**/*-test.js
+**/*-test.ts
+**/*-test.py

BinarySearch/BST-Basics.js

@@ -0,0 +1,23 @@
+## Queues
+
+Similar to Stack, Queue is another linear data structure that stores the element in a sequential manner. The only significant difference between Stack and Queue is that instead of using the LIFO method, Queue implements the FIFO method, which is short for First in First Out.
+
+A perfect real-life example of Queue: a line of people waiting at a ticket booth. If a new person comes, they will join the line from the end, not from the start — and the person standing at the front will be the first to get the ticket and hence leave the line.
+
+## Basic operations of Queue
+
+Enqueue() — Inserts element to the end of the queue
+
+Dequeue() — Removes an element from the start of the queue
+
+isEmpty() — Returns true if queue is empty
+
+Top() — Returns the first element of the queue
+
+## Commonly asked Queue interview questions
+
+Implement stack using a queue
+
+Reverse first k elements of a queue
+
+Generate binary numbers from 1 to n using a queue