LeetCode: Reverse Linked Lis

Reverse a singly linked list.

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Hint:
A linked list can be reversed either iteratively or recursively. Could you implement both?
Iterative:
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* reverseList(ListNode* head) {
if(head == NULL)
return head;
ListNode *pre = NULL;
while(head != NULL)
{
ListNode *next = head->next;
head->next = pre;
pre = head;
head = next;
}
return pre;
}
};

Recursive:
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
ListNode* reverseList(ListNode* head) {

recurse(head, NULL);
return newHead;

}
private:
void recurse(ListNode *node, ListNode *pre)
{
if(node == NULL)
return;
if(node->next == NULL)
newHead = node;
ListNode *next = node->next;
node->next = pre;
recurse(next, node);

}
ListNode *newHead;
};