How to get 5 highest values from a hashmap?

Question

I have a Hashmap that links a zipcodes stored as keys and population stored as values in a hashmap.

The hashmap contains around 33k entries.

I\'m trying to get t

Answer 1

PriorityQueue would help too, and also a nice topic about how to get top k from a list, you can check this link

PriorityQueue p = new PriorityQueue(5);

int[] a = new int[]{3,5,10,1,23,42,66,1333,545,110};

for (int i : a){
    p.add(i);
    if (p.size() > 5){
        p.poll();
    }
}

//output will be highest 5, [42, 66, 110, 1333, 545]

You can have O(n log(k)) time complexity // k is your top value count.