题解 | #反转链表#

/*
struct ListNode {
	int val;
	struct ListNode *next;
	ListNode(int x) :
			val(x), next(NULL) {
	}
};*/
class Solution {
public:
    ListNode* ReverseList(ListNode* pHead) {
        if(pHead == nullptr) return pHead;
        ListNode* pre= nullptr;
        ListNode* next= nullptr;
        while(pHead != nullptr){
            next = pHead->next;
            pHead->next = pre;
            pre = pHead;
            pHead = next;
        }
        return pre;
    }
};

原地逆置:从头节点开始，依次将节点置于之前