JavaAlgorithms/Misc/MedianOfRunningArray.java
2020-10-24 10:23:28 +00:00

47 lines
1.1 KiB
Java

package Misc;
import java.util.Collections;
import java.util.PriorityQueue;
/** @author shrutisheoran */
public class MedianOfRunningArray {
private PriorityQueue<Integer> p1;
private PriorityQueue<Integer> 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() + " ");
}
}
}