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src/data-structures/priority-queue/README.md

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+# Priority Queue
+
+In computer science, a priority queue is an abstract data type 
+which is like a regular queue or stack data structure, but where 
+additionally each element has a "priority" associated with it. 
+In a priority queue, an element with high priority is served before 
+an element with low priority. If two elements have the same 
+priority, they are served according to their order in the queue.
+
+While priority queues are often implemented with heaps, they are 
+conceptually distinct from heaps. A priority queue is an abstract 
+concept like "a list" or "a map"; just as a list can be implemented
+with a linked list or an array, a priority queue can be implemented
+with a heap or a variety of other methods such as an unordered 
+array.
+
+
+
+## References
+
+[Wikipedia](https://en.wikipedia.org/wiki/Priority_queue)