boj 1655: 가운데를 말해요

시간초과를 해결하기 위해 사용

• BufferdReader
• StringBuilder

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

public class Main {
	public static void main(String[] args) throws Exception {
		PriorityQueue<Integer> maxQueue = new PriorityQueue<>();
		PriorityQueue<Integer> minQueue = new PriorityQueue<>((o1, o2) -> o2.compareTo(o1));

		StringBuilder sb = new StringBuilder("");
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int N = Integer.parseInt(br.readLine());
		for (int i = 0; i < N; i++) {
			int num = Integer.parseInt(br.readLine());
			maxQueue.add(num);
			if ((maxQueue.size() + minQueue.size()) % 2 != 0) {
				minQueue.add(maxQueue.poll());
			} else {
				if (minQueue.peek() > num) {
					maxQueue.add(minQueue.poll());
					minQueue.add(maxQueue.poll());
				}
			}
			sb.append(minQueue.peek() + "\n");
		}

		System.out.println(sb);
	}
}