Add day 45

Author: MadhavBahl

README.md

@@ -72,6 +72,7 @@ Motivate yourself to code daily till 60 days, and see the magic! Coding will bec
 | [Day 42](./day42) | [Alternate Queue Combination](./day42) | [http://codetoexpress.tech/dc/day42/](http://codetoexpress.tech/dc/day42/) | **intermediate** |
 | [Day 43](./day43) | [Queue Reversal](./day43) | [http://codetoexpress.tech/dc/day43/](http://codetoexpress.tech/dc/day43/) | **intermediate** |
 | [Day 44](./day44) | [Queue from Stacks](./day44) | [http://codetoexpress.tech/dc/day44/](http://codetoexpress.tech/dc/day44/) | **intermediate** |
+| [Day 45](./day45) | [Priority Queue](./day45) | [http://codetoexpress.tech/dc/day45/](http://codetoexpress.tech/dc/day45/) | **intermediate** |
 
 ## [More Problems](./BONUS/README.md)
 

day44/ques.png

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+// To Be Added

day45/JavaScript/priorityQueue.js

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+![cover](./cover.png)
+
+# Day 45 - Implement a priority queue
+
+Implement the Priority Queue data structure 
+
+### Priority Queue
+
+Priority Queue is an extension of queue with following properties
+
+1. Every item has a priority associated with it.
+2. An element with high priority is dequeued before an element with low priority.
+3. If two elements have the same priority, they are served according to their order in the queue.
+
+A typical priority queue supports following operations.
+
+1. **insert(item, priority):** Inserts an item with given priority.
+2. **getHighestPriority():** Returns the highest priority item.
+3. **deleteHighestPriority():** Removes the highest priority item
+
+[Read More (Geeks4Geeks)](https://www.geeksforgeeks.org/priority-queue-set-1-introduction/)
+
+## Solution
+
+## JavaScript Implementation
+
+### [Solution](./JavaScript/priorityQueue.js)
+
+```js
+// To Be Added
+```