[백준] 자바 문제 풀이 13975 : 골드4

BOJ 13975 : 파일합치기3

import java.util.PriorityQueue;
import java.io.*;
import java.util.StringTokenizer;

public class Main {

    public static void main(String[] args) throws Exception {
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        int test_case = Integer.parseInt(br.readLine());
        PriorityQueue<Long> pq;
        StringTokenizer str;

        for (int i = 0; i < test_case; i++) {
            int size = Integer.parseInt(br.readLine());
            str = new StringTokenizer(br.readLine());
            pq = new PriorityQueue<>();
            for (int k = 0; k < size; k++) {
                pq.add(Long.parseLong(str.nextToken()));
            }
            long cost = 0;
            while (pq.size() > 2) {
                long new_num = pq.poll() + pq.poll();
                pq.add(new_num);
                cost += new_num;
            }
            cost += (pq.poll() + pq.poll());
            bw.write(Long.toString(cost) + '\n');
            bw.flush();
            pq.clear();
        }
        bw.close();
        br.close();
    }
}