合并两个有序链表

#include <iostream>using namespace std;class List{public:    int data;    List *next;};void create(List *L){    List *p = new List;    cin >> p->data;    while (p->data != 0)    {        p->next = NULL;        L->next = p;        L = L->next;        p = new List;        cin >> p->data;    }    p->next = NULL;}List* merge(List* L1, List* L2){    if (L1 == NULL)        return L2;    else if (L2 == NULL)        return L1;    List* pMerge = NULL;    if (L1->data<L2->data)    {        pMerge = L1;        pMerge->next = merge(L1->next, L2);    }    else    {        pMerge = L2;        pMerge->next = merge(L1, L2->next);    }    return pMerge;}void show(List *L){    List* p = L->next;    while (p)    {        cout << p->data << " ";        p = p->next;    }    cout << endl;}int main(){    List* L1 = new List;    List* L2 = new List;    List* lMerge = new List;    L1->next = NULL;    L2->next = NULL;    lMerge = NULL;    create(L1);    show(L1);    create(L2);    show(L2);    lMerge = merge(L1, L2);    show(lMerge);    return 0;}