Data Structures

tags: Algorithm,Data Structures Make my best effort to move to Nanjing for my son. This is a successor of LeetCode101.

tags: Data Structures,Algorithm

tags: Data Structures

tags: Heap (data structure),Data Structures,Complete Binary Tree,Tree source: https://en.wikipedia.org/wiki/Binary%5Fheap Binary tree with two additional constraints: Shape property: complete binary tree. Heap property: the key stored in each node is greater or equal(max-heaps) to or less than or equal to(min-heaps) the keys in the node’s children, according to some total order. Heap operations Insert Steps to add an element to a heap: Add element to the bottom level of the heap at the leftmost open space....

tags: Data Structures,Heap (data structure) The priority queue is solved: The K smallest/largest/weakest X.

tags: Data Structures,Tree WHAT is a heap? Tree-based data structure which is essentially an almost complete tree that statifies the heap property. Max heap For any given node C, if P is a parent node of C, then the key(the value) of P is greater than or equal to the key of C. Min heap The P is less than or equal to the key C. When to use a heap?...

tags: Data Structures,Stack source: “Monotonic Stack.” Accessed March 13, 2022. https://liuzhenglaichn.gitbook.io/algorithm/monotonic-stack. A monotonic stack is a stack whose elements are monotonically increasing or descreasing. It’s not only about the order in the stack, it’s also about remove larger/smaller elements before pushing. Monotonically descreasing we need to pop smaller elements from the stack before pushing a new element: vector<int> nums; // fill nums stack<int> st; for (auto i = nums.size() - 1; i >= 0; i--) { while (!...

tags: Data Structures,Binary Tree,Tree

tags: C/C++,Java,Data Structures In C++ the set container is an ordered or sorted set, unordered_set is the normal set in C++. Differences between them please check set vs unordered_set in C++ STL. In Java there is an java.util.SortedSet interface.

tags: Data Structures

tags: Data Structures

tags: Data Structures

tags: Data Structures

tags: Algorithm,Data Structures 又要开始找工作了，刷题、刷题、刷题！步骤： 按顺序找到题目 解题/学习 总结考察的点（树、双指针、回溯、DP、模拟现实、递归） 刷相同解法框架的题 一些模糊的感觉： 尝试不同的遍历顺序可能是解题关键，正序遍历不行试一下反序遍历，反之亦然！ 以上到达一定量之后在 LeetCode 创建一个新的 session 重新刷起。

tags: Algorithm,Data Structures,Binary Search Tree 分为三种：前序、后序和中序，其中最容易用栈改写的是后序。 前序(Preorder)：Root -> Left -> Right class Solution { public: void processPreorderTraversal(TreeNode* root, vector<int> & collector) { if (root == nullptr) { return; } processPreorderTraversal(root->left, collector); collector.push_back(root->val); processPreorderTraversal(root->right, collector); } vector<int> inorderTraversal(TreeNode* root) { vector<int> ret; if (root == nullptr) { return ret; } processPreorderTraversal(root, ret); return ret; } }; 中序(Inorder): Left -> Root -> Right class Solution { public: void processInorderTraversal(TreeNode* root, vector<int> & collector) { if (root == nullptr) { return; } processInorderTraversal(root->left, collector); collector....