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    public static void main(String[] args) {
        int[] counts = new int[]{0,0,0,0,0,0};    //경우의수를 각각 카운트(검산용)(arr 배열이 3개일때만 가능)
        Random rand = new Random(System.currentTimeMillis());

        for (int loop = 0; loop < 100000; loop++) {
            int[] arr = new int[]{0,1,2};//new int[]{0,1,2,3,4,5,6,7,8,9}; //arr.length가 3개일때 보다는 100개쯤 될때 필요한 알고리즘임
            for (int i=0; i<arr.length*2; i++) {    //2배수만큼 돌려야 골고루 잘 섞임
                int idx1 = rand.nextInt(arr.length);
                int idx2 = rand.nextInt(arr.length);
               
                if (idx1 == idx2) continue;
               
                int temp = arr[idx1];
                arr[idx1] = arr[idx2];
                arr[idx2] = temp;
            }
           
    //        for (int i=0; i<arr.length; i++) {
    //            System.out.println(arr[i]);
    //        }
           
            //경우의수 카운트(arr 배열이 3개일때만 가능)
            if (arr[0] == 0 && arr[1] == 1 && arr[2] == 2) counts[0]++;
            if (arr[0] == 0 && arr[1] == 2 && arr[2] == 1) counts[1]++;
            if (arr[0] == 1 && arr[1] == 0 && arr[2] == 2) counts[2]++;
            if (arr[0] == 1 && arr[1] == 2 && arr[2] == 0) counts[3]++;
            if (arr[0] == 2 && arr[1] == 0 && arr[2] == 1) counts[4]++;
            if (arr[0] == 2 && arr[1] == 1 && arr[2] == 0) counts[5]++;
        }
       
        for (int i=0; i<counts.length; i++) {
            System.out.println(counts[i]);
        }
       
//      출력 결과
//      16725
//      16484
//      16750
//      16803
//      16461
//      16777
    }