/**

* @auther: WJoe

* @Description

* @Date : 16:35 2018/10/16

*/

import java.util.Scanner;

class ListNode {

int val;

ListNode next;

public ListNode(int x) {

this.val = x;

}

}

public class Main {

ListNode head = null;

public void add(int data) {

ListNode newNode = new ListNode(data);

//添加头结点

if (head == null) {

head = newNode;

return;

}

ListNode temp = head;

while (temp.next != null) {

temp = temp.next;

}

temp.next = newNode;

}

public void printNode(ListNode head) {

ListNode temp = head;

while (temp != null) {

System.out.print(temp.val + " ");

temp = temp.next;

}

}

public ListNode mergeTwoLists(ListNode l1, ListNode l2) {

if (l1 == null) {

return l2;

}

if (l2 == null) {

return l1;

}

ListNode list = null;

if (l1.val < l2.val) {

list = l1;

list.next = mergeTwoLists(l1.next, l2);

} else {

list = l2;

list.next = mergeTwoLists(l1, l2.next);

}

return list;

}

public static ListNode DeleteDupliacateNode1(ListNode head) {

ListNode pPre = head;

ListNode pCur = pPre.next;

ListNode pNext;

boolean bDup;

while (pCur != null) {

pNext = pCur.next;

bDup = false;

while (pNext != null && pCur.val == pNext.val) {

pPre.next = pNext;

pCur = pNext;

pNext = pCur.next;

bDup = true;

}

if (bDup)//pCur与原数据重复，删除

{

pPre.next = pNext;

} else {

pPre = pCur;//pCur没有重复，将pPre向后移动

}

pCur = pNext;

}

return head;

}

public static void main(String[] args) {

Scanner fin = new Scanner(System.in);

int n = fin.nextInt();

int m = fin.nextInt();

Main l1 = new Main();

for (int i = 0; i < n; i++) {

l1.add(fin.nextInt());

}

Main l2 = new Main();

for (int i = 0; i < m; i++) {

l2.add(fin.nextInt());

}

ListNode list = l1.mergeTwoLists(l1.head, l2.head);

Main merge = new Main();

merge.printNode(DeleteDupliacateNode1(list));

}

}