[个人算法学习]单链表反转（带头）

typedef int ElemType;

typedef struct LNode {
	ElemType data;
	struct LNode* next; 
	int Length;
}LNode, * LinkList;

int InitList(LinkList& L) {
	L = (LNode*)malloc(sizeof(LNode));
	if (L == NULL)
		return 0;
	L->next = NULL;
	L->data = 0;
	L->Length = 0;
	return 1;
}//初始化单链表

int SetList(LinkList& L, int n) {
	InitList(L);
	for (int j = n; j > 0; j--) {
		LNode* p = (LNode*)malloc(sizeof(LNode));
		if (!p) return 0;
		cin >> p->data;
		p->next = L->next;
		L->next = p;
		L->Length++;
	}
	cout << "输入完毕" << endl;
	return 1;
}

void ShowList(LinkList& L) {
	LNode* p;
	p = L->next;
	while (p != NULL) {
		cout << p->data << "  ";
		p = p->next;
	}
	cout << "展示完毕" << L->Length << endl;
}

void RevealList1(LinkList &L) {
	LNode* next = NULL;
	LNode* pre = NULL;
	LNode* p = L->next;
	for(int i=0;i< L->Length;i++)
	{
		next = p->next;
		p->next = pre;
		pre = p;
		p = next;
	}
	L->next = pre;//此时的P和Next都为空，所以指向pre而不是P或Next
}//链表反转 迭代

LinkList Recursion(LNode *L) {
	if (L->next == NULL||L == NULL) {
		return L;
	}
	LNode* head = Recursion(L->next);
	L->next->next = L;
	L->next = NULL;
	return head;
}
void RevealList2(LinkList& L) {
	L->next = Recursion(L->next);
 }//链表反转 递归

int main() {
	LinkList L1;
	SetList(L1,4);
	ShowList(L1);
	//RevealList1(L1);
	//RevealList2(L1);
	ShowList(L1)；
	system("pause");
	return 0;
}