import java.util.Collections; import java.util.PriorityQueue; /********************** author: shrutisheoran ***********************/ public class MedianOfRunningArray { private PriorityQueue p1; private PriorityQueue p2; //Constructor public MedianOfRunningArray() { this.p1 = new PriorityQueue<>(Collections.reverseOrder()); //Max Heap this.p2 = new PriorityQueue<>(); //Min Heap } /* Inserting lower half of array to max Heap and upper half to min heap */ public void insert(Integer e) { p2.add(e); if(p2.size() - p1.size() > 1) p1.add(p2.remove()); } /* Returns median at any given point */ public Integer median() { if(p1.size()==p2.size()) return (p1.peek() + p2.peek())/2; return p1.size()>p2.size() ? p1.peek() : p2.peek(); } public static void main(String[] args) { /* Testing the median function */ MedianOfRunningArray p = new MedianOfRunningArray(); int arr[] = {10, 7, 4, 9, 2, 3, 11, 17, 14}; for(int i = 0 ; i < 9 ; i++) { p.insert(arr[i]); System.out.print(p.median() + " "); } } }