思路：日常递归
每k个完成操作，递归一次
# include<iostream> # include<vector> # include<string> # include<algorithm> # include<math.h> # include<climits> # include<stack> # include<queue> using namespace std; struct ListNode { int val; ListNode *next; ListNode() : val(0), next(nullptr) {} ListNode(int x) : val(x), next(nullptr) {} ListNode(int x, ListNode *next) : val(x), next(next) {} }; ListNode* DIGUIreverseKGroup(ListNode* head, int k) { int num=0; ListNode* p=head;//游标 ListNode* s;//反转链尾 ListNode* sh;//反转链头 if (!head)return head;//空表 if (head && k <= 1)return head; while (p&&num<k) { num++; p = p->next; } if (num < k) return head;//说明结点数不够 else {//说明节点数够的 s = head;//反转后的尾巴 sh = head; p = head->next;//游标 num = 1; while (num < k) { num++; head = p->next; p->next = sh; sh = p; p = head; }//反转 s->next = DIGUIreverseKGroup(head, k); return sh;//新头 } } ListNode* reverseKGroup(ListNode* head, int k) { head = DIGUIreverseKGroup(head, k); return head; } int main(void) { ListNode* head = new ListNode(1, new ListNode(2, new ListNode(3, new ListNode(4, new ListNode(5))))); head = reverseKGroup(head, 1);//k可以随便改 1就是k ListNode* p = head; while (p) { cout << p->val << " "; p = p->next; } cout << endl; system("pause"); return 0; }
