liuxinglin的专栏

vector preorderTraversal(TreeNode *root){vector result;stack s;if (root == NULL)return result;s.push(root); //将根节点入栈while (!s.empty()){TreeNode *p = s.top();result.push_back(p->val);s.pop();if (p->rig

使用C++中的pair类型来存储树的节点和它的层数vector > levelOrder(TreeNode *root){ vector > vec; if (root == NULL) return vec; queue > queue; pair pair(root, 0); //根节点是第0层 queue.pu

vector inorderTraversal(TreeNode *root){ vector result; if (root == NULL) return result; stack s; TreeNode *p = root; while (p || !s.empty()) { while

迭代实现：ListNode *reverseList(ListNode *head){ if (head == NULL || head->next == NULL) return head; ListNode *pCurr = head; ListNode *pPrev = NULL; ListNode *pNext = NULL; while (pCurr != NUL

ListNode *reverseBetween(ListNode* head, int m, int n) { if (m == n) return head; n -= m; ListNode prehead(0); prehead.next = hea