题解 | #反转链表#

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

/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 * 
 * @param head ListNode类 
 * @return ListNode类
 */
struct ListNode* ReverseList(struct ListNode* head ) {
    
    struct ListNode* phead=head;
   struct ListNode*pn=head->next;
   int num;
   while(phead!=NULL)
   {
    while(pn!=NULL)
    {
        num=phead->val;
        phead->val=pn->val;
        pn->val=num;
        pn=pn->next;

    } 
    phead=phead->next;
    pn=phead->next;
   }
   return head;
    
    // write code here
}