Data Structures

Sparse Table

Keywords: range minimum query

Sparse Table

Segment Tree

Keywords: binary tree, range sum, range minimum, segment change

參考資料

Leetcode 456: 132 Pattern

Difficulty: Medium (8 personal rank)
Keywords: stack

Stack and Simple Calculator

Keyword: Stack, Calculator

Leetcode208: Implement Trie (Prefix Tree)

Difficulty: Medium (1 personal rank)
Keyword: Trie, prefix tree, word search

題目

Implement a trie with insert, search, and startsWith methods.

Binary Search Tree and AVL Tree

Keyword: BST, AVL(Adelson-Velsky and Landis) Tree

二元搜尋樹 (BST)

二元搜尋樹（英語：Binary Search Tree），也稱為有序二元樹（ordered binary tree）或排序二元樹（sorted binary tree），是指一棵空樹或者具有下列性質的二元樹：

• 若任意節點的左子樹不空，則左子樹上所有節點的值…

Leetcode 1505: Minimum Possible Integer After at Most K Adjacent Swaps On Digits

Difficulty: Hard (9 personal rank)
Keyword: BIT, segment tree, double-ended queue(deque)

題目

Given a string num…

Leetcode 295: Find Median from Data Stream

Difficulty: Hard (7 personal rank)
Keyword: priority queue

前言

這題早就寫過，但是實隔許久再寫直覺依然是binary insertion。答案雖然簡單，但並不是容易內化的題目。

題目