高手们帮小弟看一下小弟写的关于用链表实现集合的合.并.差出现异常，在线等

#include <iostream.h>

#include <stdlib.h>

typedef struct List//节点的定义

{

	int data;

	struct List *next;

}List,* Link;

void CreateList(Link head)//创建链表

{

	head=(Link)malloc(sizeof(List));

	head->next=NULL;

	while (1)

	{

		Link pointor=(Link)malloc(sizeof(List));

		cin>>pointor->data;

        if(!cin)//判断是否为字符

		 {

           cin.clear();

           cin.get();

           continue;

		 } 

		else

		{

			break;

		}

        pointor->next=head->next;

		head->next=pointor;

	}

}

void PrintList(Link head)

{

	Link newhead=head->next;

    do

    {

       cout<<newhead->data<<" ";

	   newhead=newhead->next;

    }while (newhead->next!=NULL); 

}

void SetIntersection(Link head1,Link head2)//集合的交集

{

   for(Link p=head1->next;p!=NULL;p=p->next)

   for(Link q=head2->next;q!=NULL;q=q->next)

   {

	   if (p->data==q->data)

	   {

		   cout<<p->data<<" ";

	   }

   }

   cout<<endl;

}

void SetAltogeter(Link head1,Link head2)//集合并集

{

	for (Link p=head1->next;p!=NULL;p=p->next)

	{

		for (Link q=head2->next;q!=NULL;q=q->next)

		{

			if(p->data!=q->data)

			{

			 cout<<p->next<<" ";	

			}

		}

	}

		   PrintList(head2);

		   cout<<endl;

}

void SetMission(Link head1,Link head2)//集合的差

{

	cout<<"Head1-Head2:"<<endl;

	for (Link p=head1->next;p!=NULL;p=p->next)

	{

		for (Link q=head2->next;q!=NULL;q=q->next)

		{

			if (p->data!=q->data)

			{

				cout<<p->data<<" ";

			}

		}

	}

	cout<<endl;

	cout<<"Head2-Head1"<<endl;

	for (Link m=head2->next;m!=NULL;m=m->next)

	{

		for (Link n=head1->next;n!=NULL;n=n->next)

		{

			if (m->data!=n->data)

			{

				cout<<m->data<<" ";

			}

		}

	}

	cout<<endl;

}

void main()

{

	Link head1;

	Link head2;

	cout<<"创建列表Head1:"<<endl;

	CreateList(head1);

	cout<<"创建列表Head2:"<<endl;

	CreateList(head2);

	cout<<"集合的交集:"<<endl;

	SetIntersection(head1,head2);

	cout<<"集合的并集:"<<endl;

	SetAltogeter(head1,head2);

	cout<<"集合的差:"<<endl;

	SetMission(head1,head2);

}

小弟初学，编译能通过就是建立第一个链表后第二个就出现异常了啊！望高手帮忙指正，谢谢！
编译情况：
创建列表Head1:
1 2 3 4
创建列表Head2:
集合的交集:
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