LintCode/35.h at master · scially/LintCode · GitHub

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/**
 * Definition of ListNode
 *
 * class ListNode {
 * public:
 *     int val;
 *     ListNode *next;
 *
 *     ListNode(int val) {
 *         this->val = val;
 *         this->next = NULL;
 *     }
 * }
 */


class Solution {
public:
    /*
     * @param head: n
     * @return: The new head of reversed linked list.
     */
    ListNode * reverse(ListNode * head) {
        // write your code here
        ListNode *prev = nullptr;
        while(head != nullptr){
            ListNode *next = head->next;
            head->next = prev;
            prev = head;
            head = next;
        }
        return prev;
    }
};