[백준 11286] 절대값 힙 구현(우선순위 큐-중요)

🔗 문제

https://www.acmicpc.net/problem/11286

11286번: 절댓값 힙

 

💡 힌트

우선순위 큐 이론 참조

Java 우선순위 큐(Priority Queue) 와 Comparable, Comparator – Jihun's Development Blog (cjh5414.github.io)

 

💻 코드

package org.kyhslam.DoItAlgorithm.ch02;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.PriorityQueue;

public class p11286 {
    public static void main(String[] args) throws IOException {

        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int N = Integer.parseInt(br.readLine());

        PriorityQueue<Integer> myQueue = new PriorityQueue<>( (o1, o2) -> {
            int first_abs = Math.abs(o1);
            int second_abs = Math.abs(o2);

            if (first_abs == second_abs) {
                return o1 > o2 ? 1 : -1;
            } else {
                return first_abs - second_abs;
            }
        });

        for (int i = 0; i < N; i++) {
            int request = Integer.parseInt(br.readLine());
            if (request == 0) {

                if (myQueue.isEmpty()) {
                    System.out.println("0");
                } else {
                    System.out.println(myQueue.poll());
                }
            } else {
                myQueue.add(request);
            }
        }

    }
}