链表创建与翻转

#include
using namespace std;

typedef struct ListNode
{
	int val;
	struct ListNode *next;
	ListNode(int x) : val(x), next(NULL) {}
} ListNode, *LinkList;

class Solution
{
public:
	ListNode* ReverseList(ListNode* pHead)
	{
	ListNode *prev = NULL;
	while (pHead != NULL)
	{
		ListNode *temp = pHead->next;
		pHead->next = prev;
		prev = pHead;
		pHead = temp;
	}
	return prev;
}
	void CreatList(LinkList &L, int n)
	{
		LinkList q, p;
		//      L=(LinkList)malloc(sizeof(ListNode));
		L = new ListNode(NULL);
		//       L->next=NULL;//创建一个不带带头结点的单链表
		p = L; //L为头结点
		if (n>0) cin >> p->val;
		int x;
		for (int i = 0; i> x;
			q = new ListNode(x);

			p->next = q;
			p = q;
		}
		//p->next = NULL;
	}

};
int main()
{
	Solution so;
	int n;
	cin >> n;
	ListNode* L;
	so.CreatList(L, n);

	
	ListNode* ans = so.ReverseList(L);
	
	cout << endl;
	while (ans)
	{
		cout << ans->val << endl;
		ans = ans->next;
	}
	system("pause");
	return 0;
}

链表翻转步骤：

假设pre之前已经翻转完成

将p.next指向pre完成当前节点的翻转；

将pre 和p后移