Problem:
MathJax.Hub.Config({ tex2jax: { inlineMath: [["$","$"], ["\\(","\\)"]], processEscapes: true }});

Priority Queue

A priority queue is a data structure which maintains a set $S$ of elements, each of with an associated value (key), and supports the following operations:

$insert(S, k)$: insert an element $k$ into the set $S$

$extractMax(S)$: remove and return the element of $S$ with the largest key

Write a program which performs the $insert(S, k)$ and $extractMax(S)$ operations to a priority queue $S$.
The priority queue manages a set of integers, which are also keys for the priority.

Input

Multiple operations to the priority queue $S$ are given. Each operation is given by "insert $k$", "extract" or "end" in a line. Here, $k$ represents an integer element to be inserted to the priority queue.

The input ends with "end" operation.

Output

For each "extract" operation, print the element extracted from the priority queue $S$ in a line.

Constraints

The number of operations $\leq 2,000,000$

$0 \leq k \leq 2,000,000,000$

Sample Input 1

insert 8
insert 2
extract
insert 10
extract
insert 11
extract
extract
end

Sample Output 1

8
10
11
2

Solution in JAVA (judge verdict: Accepted)

import java.util.*;
import java.io.*;

class Main {

	static int size;

	public static void main(String[] args) throws IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		PriorityQueue<Integer> pQue = new PriorityQueue<Integer>(10,COMPARATOR);

		while (true) {
			String line = br.readLine();
			if (line.equals("end")){
				break;
			}else if (line.startsWith("insert")) {
				pQue.add(Integer.parseInt(line.substring(line.indexOf(" ")+1)));
			}else {
				System.out.println(pQue.poll());
			}

		}
	}

	public static final Comparator<Integer> COMPARATOR = new Comp();
	
	private static class Comp implements Comparator<Integer>{
		public int compare(Integer x,Integer y){
			return (x < y) ? 1 : ((x == y) ? 0 : -1);
		}
	}
}