LESSON 55 / 75·2 min readIntermediate

Heap and priority queue in .NET

Should knowConcept lesson
01 Understand02 Recall03 Prepare

PriorityQueue<T> usage

csharp
var pq = new PriorityQueue<int, int>();
pq.Enqueue(5, 5);
pq.Enqueue(3, 3);
pq.Enqueue(9, 9);
int top = pq.Peek();

Problems to practice

  • Kth largest element
  • Top K frequent elements
  • Merge K sorted lists
  • Median in stream

Interview guidance

A heap gives efficient top-element access and is often used for ordering under constraints.


PAUSE & RECALL

Can you explain it without the notes?

Heap and priority queue in .NET

Use your own words. Explain an example and one limitation before checking the explanation.

Check your explanation

PriorityQueue usage

CONNECT IT TO YOUR INTERVIEW

Turn this concept into a clear answer.

Practice this concept
YOUR NEXT STEP

Keep connecting the ideas.

Next lesson: Graphs in C#

Adapted from 17_DSA_DOTNET.md · “8. Heap and priority queue in .NET”. Examples are study fragments; framework behavior can depend on your version.