时间复杂度O（N），空间复杂度O(1) 最优解

import java.util.Arrays;
import java.util.Scanner;

/**
 * @Auther: JayV
 * @Email: javajayv@gmail.com
 * @Date: 2022-5-31 15:29
 * @Description:
 */
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        boolean[] arr = new boolean[501];
        Arrays.fill(arr, false);
        for(int i = 0; i < n; i++) {
            int num = sc.nextInt();
            arr[num] = true;
        }
        for(int i = 1; i <= 500; i++) {
            if(arr[i]) {
                System.out.println(i);
            }
        }
    }
}