Data structure to use: need to access both by priority and name

Question

What data structure to use when I need to

• access an object by priority - to dequeue
• access an object by name/id to update the priority

With Java's PriorityQueue, I can't access a node directly by its name/id property can I?

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I was thinking along the lines of use a priority queue, plus a TreeMap so I can search by name in log(n) time, then modify the priority. But I doubt the Queue will know of that? In that case, I need to remove and re-add the node? Is that worth the overhead? What complexity is it to remove/re-add a node?

Answer 1

In that case, I need to remove and re-add the node?

Yes.

Is that worth the overhead?

That depends on your requirements. Only you know that.

What complexity is it to remove/re-add a node?

Insert and remove from a PriorityQueue is O(log n).