暴力！！

这题可以暴力秒😄
先排序，定义一个数，如果等于说明是重复的，那么直接跳过，否则放入list，最后得到的就是正确答案惹

import java.awt.List;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Scanner;

public class Main
{
    public static void main(String args[])
    {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext())
        {
            int a = sc.nextInt();
            int b[] = new int[a];
            for (int i = 0; i < b.length; i++)
            {
                b[i] = sc.nextInt();
            }
            Arrays.sort(b);
            ArrayList<Integer> t = new ArrayList<Integer>();
            int x = -1;
            for (int i = 0; i < b.length; i++)
            {
                if (x == b[i])
                {
                    continue;
                }
                t.add(b[i]);
                x=b[i];
            }
            System.out.println(t.size());
for (int i = 0; i <t.size(); i++)
{
    if (i==0)
    {
        System.out.print(t.get(i));
    }else {
        System.out.print(" "+t.get(i));
    }
}
System.out.println();

        }

    }
}