To be the master at Graphs and Heap is just practice the questions, But one thing which should be done that your level of interest in that topic, get your concept clear, be active on leetcode with graphs question & heap questions.

here are few questions which you can do for being master at Graphs & Heaps

• Heaps:-

1. Second largest element in array
2. Kth largest element in array
3. Sort characters by its frequency
4. Graph the Graphs question like Find Shortest path
5. etc..........