题解 | #反转链表#

js

    this.val = x;
    this.next = null;
}*/
function ReverseList(pHead)
{
    // write code here
    if(!pHead || !pHead.next){
        return pHead
    }
    let pre = null
    let cur = null
    while(pHead){
        cur = pHead.next
        pHead.next = pre
        pre = pHead
        pHead = cur
    }
    return pre
}
module.exports = {
    ReverseList : ReverseList
};

C语言

 * struct ListNode {
 *	int val;
 *	struct ListNode *next;
 * };
 */

/**
 * 
 * @param pHead ListNode类 
 * @return ListNode类
 */
struct ListNode* ReverseList(struct ListNode* pHead ) {
    // write code here
    if(pHead == NULL)
        return NULL;
    struct ListNode*temp = NULL;
    struct ListNode*pre = NULL;
    while(pHead != NULL){
        temp = pHead->next;
        pHead -> next = pre;
        pre = pHead;
        pHead = temp;
   }
    return pre;
}