최빈값 구하기

/* 최빈값 구하기

 * 최빈값은 주어진 값 중에서 가장 자주 나오는 값을 의미합니다.

 * 정수 배열 array가 매개변수로 주어질 때, 최빈값을 return

 * 최빈값이 여러 개면 -1을 return 합니다.

 *

 * array                result

 * [1, 2, 3, 3, 3, 4]   3

 * [1, 1, 2, 2]         -1

 * [1]                  1

 */

 

import java.util.*;
public class Programmer_0_33 {
    static int[] a1 = {1, 2, 3, 3, 3, 4};
    static int[] a2 = {1, 1, 2, 2};
    static int[] a3 = {1};
 
    public int getChk(List<Map<String,Object>> listAr, int val){
        int chk = 0;
 
        for(Map<String,Object> mp : listAr){
            if(mp.get("val").equals(val))   chk++;
        }
 
        return chk;
    }
 
    public int solution(int[] array) {
        int answer = 0;
 
/*      다른사람 풀이
        int maxCount = 0;
        int answer = 0;
        Map<Integer, Integer> map = new HashMap<>();
        for(int number : array){
            int count = map.getOrDefault(number, 0) + 1;
            if(count > maxCount){
                maxCount = count;
                answer = number;
            }
            else  if(count == maxCount){
                answer = -1;
            }
            map.put(number, count);
        }
 */
 
        Arrays.sort(array);
        List<Map<String, Object>> rstAr = new ArrayList<Map<String, Object>>();
        int max = 0;
 
        for(int i = 0; i < array.length; i++){
            Map<String, Object> rstMp = new HashMap<String, Object>();
            int cnt = 0;
            for(int k = 0; k < array.length; k++){
                if(array[i] == array[k])    cnt++;
            }
            if(getChk(rstAr, array[i]) == 0){
                rstMp.put("val", array[i]);
                rstMp.put("cnt", cnt);
                rstAr.add(rstMp);
            }
        }
        for(int i = 0; i < rstAr.size(); i++){
            System.out.println(rstAr.get(i));
        }
 
        
        for(int i = 0; i < rstAr.size(); i++){
            Map<String, Object> mp = rstAr.get(i);
            if((int)mp.get("cnt") > max){
                max = (int) mp.get("cnt");
                answer = (int)mp.get("val");
            } 
        }
 
        int chk = 0;
        for(Map<String,Object> tst : rstAr){
            if(max == (int) tst.get("cnt")) chk++;
        }
        if(chk > 1) answer = -1;
        
        return answer;
    }
    public static void main(String args[]){
        Programmer_0_33 t = new Programmer_0_33();
 
        System.out.println("---------------------------------------");
        System.out.println("result = " + t.solution(a1));
        System.out.println("---------------------------------------");
        System.out.println("result2 = " + t.solution(a2));
        System.out.println("---------------------------------------");
        // System.out.println("result3 = " + t.solution(a3));
        // System.out.println("---------------------------------------");
    }
}