题解 | #链表中的节点每k个一组翻转#

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

class Solution {
public:
    /**
     * 
     * @param head ListNode类 
     * @param k int整型 
     * @return ListNode类
     */
    ListNode* reverseKGroup(ListNode* head, int k) {
        // write code here
        ListNode* tail = head;
        for(int i = 0;i<k;i++)
        {
            if(tail == NULL)
            {
                return head;
            }
            tail = tail->next;
        }
        ListNode* pre = NULL;
        ListNode* cur = head;
        while(cur!=tail)
        {
            ListNode* temp = cur->next;
            cur->next = pre;
            pre = cur;
            cur = temp;
        }

        head->next = reverseKGroup(tail,k);
        return pre;     
    }
};

需二刷熟悉思路