题解 | #明明的随机数#

import java.util.*;
// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        HashSet<Integer> set = new HashSet<>();
        Scanner in = new Scanner(System.in);
        int N = in.nextInt();
        int[] arr = new int[N];
        for(int i = 0;i < N;++i){
            arr[i] = in.nextInt();
        }

        for(int num : arr){
            Integer i = new Integer(num);
            set.add(i);
        }

        int[] array = new int[set.size()];
        int index = 0;
        for(Integer n : set){
            array[index++] = n.intValue();
        }

        quickSort(array,0,array.length-1);
        for(int i = 0;i<array.length;++i){
            System.out.println(array[i]);
        }

    }

    public static void quickSort(int[] arrs, int start, int end){
        int low = start,high = end;
        if(start < end){
            int guard = arrs[start];
            while (low != high){
                while(low < high && arrs[high] >= guard){
                    high--;
                }
                while(low < high && arrs[low] <= guard){
                    low++;
                }
                if(low < high){
                    int temp = arrs[low];
                    arrs[low] = arrs[high];
                    arrs[high] = temp;
                }
            }
            arrs[start] = arrs[low];
            arrs[low] = guard;
            quickSort(arrs,start,low-1);
            quickSort(arrs,low+1,end);
        }
    }

}