两个有序链表序列的交集

#pragma warning(disable:4996)
#include <stdio.h>

typedef struct Node * List;

struct Node
{
	int data;
	List next;
};

List Create();
List Cul(List L1,List L2);

int main()
{
	List L1, L2, L3;
	L1 = Create();
	L2 = Create();
	L3 = Cul(L1,L2);
	if(L3)
	{ 
		printf("%d", L3->data);
		L3 = L3->next;
		while (L3)
		{
			printf(" %d",L3->data);
			L3 = L3->next;
		}
	}
	else
	{
		printf("NULL");
	}
	return 0;
}

List Create()
{
	List L,t,cycle;
	int a;
	scanf("%d",&a);
	L = (List)malloc(sizeof (struct Node));
	t = L;
	L->next = NULL;

	while (a!=-1)
	{
		List temp;
		temp = (List)malloc(sizeof(struct Node));
		temp->next = NULL;
		temp->data = a;
		t->next = temp;
		t = temp;
		scanf(" %d",&a);
	}
	cycle = L;
	L = L->next;
	free(cycle);
	return L;
}

List Cul(List L1,List L2)
{
	List L3,t,cycle;
	List l1, l2;
	l1 = L1;
	l2 = L2;
	L3 = (List)malloc(sizeof(struct Node));
	t = L3;
	L3->next = NULL;
	while (l1 && l2)
	{
		if (l1->data==l2->data)
		{
			List temp;
			temp = (List)malloc(sizeof(struct Node));
			temp->next = NULL;
			temp->data = l1->data;
			t->next = temp;
			t = temp;
			l1 = l1->next;
			l2 = l2->next;
		}
		else if(l1->data>l2->data)
		{
			l2 = l2->next;
		}
		else
		{
			l1 = l1->next;
		}
	}
	cycle = L3;
	L3 = L3->next;
	free(cycle);
	return L3;
}