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) { Scanner in = new Scanner(System.in); TreeSet<Integer> tree = new TreeSet<>(); int n = in.nextInt(); int[] a = new int[n]; for (int i = 0; i < n; i++) { a[i] = in.nextInt(); tree.add(a[i]); } int m = in.nextInt(); int[] b = new int[m]; for (int i = 0; i < m; i++) { b[i] = in.nextInt(); tree.add(b[i]); } for (int s : tree) { System.out.print(s); } } }