java

import java.util.*;

public class Main{
    public static void  main(String[] args){
        Scanner scanner = new Scanner(System.in);
        while(scanner.hasNext()){
            //示例中的第1个数,6
            int num =scanner.nextInt();
            //示例中的第2个数,2,头结点
            Node head = new Node(scanner.nextInt());
            num--;
            //构造题目给出的链表。
            while(num>0){
                //比如输入 1 2 , 2->1 表示在2这个节点后面插上1这个节点。
                //所以当前节点是1, 前面一个节点是2
                int cur = scanner.nextInt();
                int pre = scanner.nextInt();
                insert(head,pre,cur);
                num--;
            }
            //链表构造完成后,删除输入的指定的节点。
            int deleteVal = scanner.nextInt();
            //删除头结点2
            if(head.val == deleteVal){
                head = head.next;
            }else{
                delete(head,deleteVal);
            }
            Node test = head;
            //打印输出
            while(test != null){
                System.out.print(test.val + " ");
                test = test.next;
            }
            //千万别忘了换行!!!!!!
            System.out.println();
        }
    }

    //插入Node
    public static void insert(Node head,int preVal,int newVal){
        //要被插入的节点。
        Node newNode = new Node(newVal);
        Node cur = head;
        Node temp;
        while(cur != null){
            if(cur.val == preVal){
                temp = cur.next;
                cur.next = newNode;
                newNode.next = temp;
                return;
            }
            cur = cur.next;
        }
    }
    public static void delete(Node head,int delVal){
        Node cur = head;
        Node temp;
        while(cur.next != null){
            if(cur.next.val == delVal){
                cur.next = cur.next.next;
                return;
            }
            cur = cur.next;
        }
    }
}

//节点构造
class Node{
    int val;
    Node next;
    Node(int val){
        this.val = val;
    }
}