Kth Maximum and Minimum in an Array

Different methods to find kth max and min in an array

Photo by Karina Vorozheeva on Unsplash

Max and Min Binary Heap

1. Build a max and min-heap. It will take O(n) time.
2. Extract max and min k times.
3. Time complexity O(n + k*logN).

Sorting the Array:

1. If the given array is unsorted then sort the array in ascending order using sort() method.
2. Kth max can be obtained on the index: array.length - k
3. Kth min can be obtained on the index: k - 1
4. Time Complexity O(N logN), Space Complexity O(1)

Using Hashmap

1. We will use the javascript object as a map.
2. Store each item of the array in the map.
3. Kth max can be obtained on the index: arr.length - k
4. Kth min can be obtained on the index: k - 1
5. Time Complexity O(n), Space Complexity O(n)

Also read,

How to build max and min binary heap?

Max Binary Heap in JavaScript

Min Binary Heap in JavaScript