베스트앨범

https://programmers.co.kr/learn/courses/30/lessons/42579

제가 푼 이 코드가 정답이긴 하나 복잡하니 다른 블로그의 코드를 참고하세요.

후에 다시 풀 예정입니다.

import java.io.*;
import java.util.*;
 
public class Solution {
 
    static BufferedReader br;
    static BufferedWriter bw;
    static HashMap<String, Integer> hm = new HashMap<String, Integer>();
    static HashMap<String, Integer> Mark = new HashMap<String, Integer>();
    static Vector<Vector<pair>> v = new Vector<Vector<pair>>();
    static Vector<pair> vt = new Vector<pair>();
 
    static int[] solution(String[] genres, int[] plays) {
        int[] answer = {};
     
        int len = genres.length;
        
        for(int i=0; i<len; i++) {
            Vector<pair> temp = new Vector<pair>();
            v.add(temp);
        }
        
        for(int i=0, j=0; i<len; i++) {
            if(hm.containsKey(genres[i])) {
                hm.put(genres[i], hm.get(genres[i]) + plays[i]);
                int num = Mark.get(genres[i]);
                v.get(num).add(new pair(plays[i], i));
            }
            else {
                hm.put(genres[i], plays[i]);
                Mark.put(genres[i], j);
                v.get(j).add(new pair(plays[i], i));
                ++j;
            }
        }
        
        for(String s : hm.keySet()) {
            int num = Mark.get(s);
            int cnt = hm.get(s);         
            vt.add(new pair(cnt, num));
        }
        
        Collections.sort(vt, new Comparator<pair>() {
            public int compare(pair p1, pair p2) {
                if(p1.first < p2.first) {
                    return 1;
                }
                
                return -1;
            }
        });
 
        int vts = vt.size();
        
        System.out.println();
        
        for(int i=0; i<len; i++) {
            if(!v.get(i).isEmpty()) {
                Collections.sort(v.get(i), new Comparator<pair>() {
                    public int compare(pair p1, pair p2) {
                        if(p1.first > p2.first) {
                            return -1;
                        }
                        
                        if(p1.second > p2.second) {
                            return 1;
                        }
                            
                        return -1;
                    }
                });
 
                System.out.println("-----------------");
                for(pair p : v.get(i)) {
                    System.out.println(p.first + ", " + p.second);
                }
                System.out.println("-----------------");
            }
        }
        
        Vector<Integer> ret = new Vector<Integer>();
        
        int idx = 0;
        
        for(int i=0; i<vts; i++) {
            int number = vt.get(i).second;
            ret.add(v.get(number).get(0).second);
         
            if(v.get(number).size() >= 2) {
                ret.add(v.get(number).get(1).second);
            }
        }
        
        int rs = ret.size();
        answer = new int[rs];
        for(int i=0; i<rs; i++) {
            answer[i] = ret.get(i);
        }
        
        return answer;
    }
    
    public static void main(String[] args) throws IOException  {
        // TODO Auto-generated method stub
        br = new BufferedReader(new InputStreamReader(System.in));
        bw = new BufferedWriter(new OutputStreamWriter(System.out));
        StringTokenizer st;
        //st = new StringTokenizer(br.readLine());
        //                      0         1      2            3        4      5
//        String[] genres = { "classic", "pop", "classic", "classic", "pop", "TEST" };
//        int[] plays = {800, 800, 800, 800, 800, 5000};
        
        //                      0       1          2           3       4
        String[] genres = { "classic", "pop", "classic", "classic", "pop" };
        int[] plays = {500, 600, 150, 800, 2500};
        
        // 답 : 5 0 2 1 4
        int[] ans = solution(genres, plays);
        
        for(int i=0; i<ans.length; i++) {
            System.out.print(ans[i] + " ");
        }
        
        bw.write("\n");
        bw.flush();
        bw.close();
    }
}
 
class pair {
    int first, second;
    pair(int a, int b) {
        this.first = a;
        this.second = b;
    }
}
 
class tuple {
    int first, second, third;
    tuple(int a, int b, int c) {
        this.first = a;
        this.second = b;
        this.third = c;
    }
}
 
class PQ implements Comparable<PQ> {
    int first, second;
    
    PQ(int f, int s) {
        this.first = f;
        this.second = s;
    }
    
    public int compareTo(PQ p) {
        if(this.first < p.first) {
            return -1; // 오름차순
        }
        else if(this.first == p.first) {
            if(this.second < p.second) {
                return -1;
            }
        }
        
        return 1; 
        // 이미 this.first가 더 큰 것이 됐으므로, 1로 해준다.
        // -1로 하면 결과가 이상하게 출력됨.
    }
}