# 淡大 AI 創智社 LeetCode 讀書會規劃
規劃與執行負責人：Milo Chen
### Milo 自介
PyCon Taiwan 2022 講者
PyCon APAC 2023 講者
LeetCode: https://leetcode.com/milochen/
GitHub for LeetCode https://github.com/milochen0418/leetcode
目前是偏鄉國中教中學生一些生活科技與資訊科技
（機構、電路、簡單設計、寫程式(Web, Python, MicroPython FW/SW))
作一些企業算是科技教練。

以前是有在醫療產業、汽車產業、消費性電子
PM, 架構師, 工程師,

## 時間地點
時間預計為每個 Monday 晚上 PM07:30 ~ PM09:00
地點除特殊見面活動外，使用Google的線上軟體

## 課程分組進行方式

(1) 每周的題目會讓大家分組合作完成，但前2周的部份，都要個準備。
(2) 第3周後開始分組，每組認幾題來解題，並分享之
(3) 開始分組後，也會徵稿 Lighting Talk ，歡迎學生與業界人事分享一下業界與學界的近況
(4) 第8周是大魔王關，每組專題的方式進行，認領至少1題來作即可。想認多題的組別也歡迎。
(5) 會有實體的見面會，讓大家可以彼此分享認識交流。
(6) 分享者可以自己選擇是否分享文字、影象或是其它東西，留給一些沒來上的人看。

## 其它 Bonus

(1) 分享自己曾經在 AWS, Apple, Google 面試算法的經驗
(2) 分享一下 LeetCode 周賽的資訊，以及為何推薦打周賽
(3) 分享 LeetCode 一些高手們常用的其它資源 。
(4) 不定期邀請台灣 LeetCode 排名前面的高手們來作分享。
(5) 康樂讓大家有更多面對面或是線上交流建人脈的機會

[TOC]

# 每周的解題的細節規劃
以 Grind75 為主，但有從中篩選掉一些，標記為 Optioanl 的可作可不作

## Week 1
第一周都是Easy題，適合練基本功, 每個人都得練才可以未來分組後 team work 順利
第一周的部份會額外多點講解，解釋一個相同的題目可以有許多不同解答。

### 1. Two Sum
Approach 1. Brute Force
Approach 2. Two-pass Hash Table
Approach 3: One-pass Hash Table

### 2. Valid Parentheses
Approach 1. Stacks

### 3. Merge Two Sorted Lists
Approach 1. Recursion
Approach 2. Iteration

### 4. Best Time to Buy and Sell Stock
Approach 1. Brute Force
Approach 2. One Pass
### 5. Valid Palindrome
Approach 1. Compare with Reverse

### 6. Invert Binary Tree
Approach 1. Recursive
Approach 2. Iterative

### 7. Valid Anagram
Approach 1. Sorting
Approach 2. Frequency Counter

### 8. Binary Search
Approach 1. Find the Exact Value
Approach 2. Find Upper bound
Approach 3. Find Lower bound
Approach 4. Use built-in tools

### 9. Flood Fill
Approach 1. Depth-First Search
Approach 2. Breath-First Search
Approach 3. Union-Find

### 10. Lowest Common Ancestor of a Binary Search Tree
Approach 1. Recursive Approach
Approach 2. Iterative Approach

### 11. Balanced Binary Tree
Approach 1. Top-down recursion
Approach 2. Bottom-up recursion

### 12. Linked List Cycle
Approach 1. Hash Table
Approach 2. Floyd's Cycle Finding Algorithm

### 13. Implement Queue using Stacks
Approach 1. (Two Stacks) Push - O(n) per operation, Pop - O(1) per operation.
Approach 2. (Two Stacks) Push - O(1) per operation, Pop - O(n) per operation.

## Week 2
第二周都是Easy題，適合練基本功, 每個人都得練才可以未來分組後 team work 順利
第二周開始就換鼓勵同學的不同解答(如果有的話) 與他們的解題思維分享。
### 1. First Bad Version
Approach 1. Linear Scan (TLE)
Approach 2. Binary Search
### 2. Ransom Note
Approach 1. Simulation
Approach 2. Two HashMaps
Approach 3. One HashMap
Approach 4. Sorting and Stacks

### 3. Climbing Stairs
Approach 1. Brute Force
Approach 2. Recursion with Memorization
Approach 3. Dynamic Programming
Approach 4. Fibonacci Number
Approach 5. Binets Method
Approach 6. Fibonacci Formula

### 4. Longest Palindrome
Approach 1. Greedy

### 5. Reverse Linked List
Approach 1. Iterative
Approach 2. Recursive

### 6. Majority Element
Approach 1. Brute Force
Approach 2. HashMap
Approach 3. Sorting
Approach 4. Bit Manipulation
Approach 5. Randomization
Approach 6. Divide and Conquer
Approach 7. Boyer-Moore Voting Algorithm

### 7. Add Binary
Approach 1. Bit-by-Bit Computation
Approach 2. Bit Manipulation

### 8. Diameter of Binary Tree
Approach 1. Depth-first Search

### 9. Middle of the Linked List
Approach 1. Output to Array
Approach 2. Fast and Slow Pointer

### 10. Maximum Depth of Binary Tree
Approach 1. Recursion
Approach 2. Tail Recursion + BFS
Approach 3. Iteration

### 11. Contains Duplicate
Approach 1. Naive Linear Search(TLE)
Approach 2. Sorting
Approach 3. Hash Table

### 12. Maximum Subarray
Approach 1. Optimized Brute Force
Approach 2. Dynamic Programming, Kadane's Algorithm
Approach 3. Divide and Conquer(Advanced)

## Week 3
第三周開始就是大家分組進行的方式來分享，並提供 Lighting Talk 大家一些演講的機會交流
### 1. Insert Interval
Approach 1. Linear Search
Approach 2. Binary Search

### 2. 01 Matrix
Approach 1. Brute force(TLE)
Approach 2. Using BFS
Approach 3. Dynamic Programming

### 3. K Closest Points to Origin

Approach 1. Sort
Approach 2. Divide and Conquer

### 4. Longest Substring Without Repeating Characters

Approach 1. Brute Force
Approach 2. Sliding Window
Approach 3. Sliding Window Optimized

### 5. 3Sum
Approach 1. Two Pointers
Approach 2. Hashset
Approach 3. No Sort

### 6. Binary Tree Level Order Traversal
Approach 1. Recursion
Approach 2. Iteration

### 7. Clone Graph
Approach 1. Depth First Search
Approach 2. Breadth First Search

### 8. Evaluate Reverse Polish Notation
Approach 1. Reducing the List in-place
Approach 2. Evaluate with Stack

## Week 4
第4周也是分組進行的方式來分享，並提供 Lighting Talk 大家一些演講的機會交流
### 1. Course Schedule
Approach 1. Backtracking
Approach 2. Postorder DFS
Approach 3. Topological Sort

### 2. Implement Trie (Prefix Tree)

### 3. Coin Change

### 4. Product of Array Except Self

### 5. Min Stack (Optional)

### 6. Validate Binary Search Tree

### 7. Number of Islands

### 8. Rotting Oranges

## Week 5
第4周也是分組進行的方式來分享，並提供 Lighting Talk 大家一些演講的機會交流
### 1. Search in Rotated Sorted Array

### 2. Combination Sum

### 3. Permutations

### 4. Merge Intervals

### 5. Lowest Common Ancestor of a Binary Tree

### 6. Time Based Key-Value Store

### 7. Accounts Merge (Optional)

### 8. Sort Colors (Optional)

## Week 6
第4周也是分組進行的方式來分享，並提供 Lighting Talk 大家一些演講的機會交流
### 1. Word Break

### 2. Partition Equal Subset Sum (Optional)

### 3. String to Integer (atoi)

### 4. Spiral Matrix

### 5. Subsets

### 6. Binary Tree Right Side View (Optional)

### 7. Longest Palindromic Substring (Optional)

### 8. Unique Paths

### 9. Construct Binary Tree from Preorder and Inorder Traversal (Optional)

## Week 7
第4周也是分組進行的方式來分享，並提供 Lighting Talk 大家一些演講的機會交流
### 1. Container With Most Water

### 2. Letter Combinations of a Phone Number

### 3. Word Search

### 4. Find All Anagrams in a String

### 5. Minimum Height Trees (Optional)

### 6. Task Scheduler (Optional)

### 7. LRU Cache (Optional)

## Week 8
第8周也是分組進行的方式來分享，但因為是Hard 題
所以提供大家可認領1至2題來分享即可。最後仍然有提供 Lighting Talk 大家一些演講的機會交流
### 1. Kth Smallest Element in a BST

### 2. Minimum Window Substring

### 3. Serialize and Deserialize Binary Tree

### 4. Trapping Rain Water

### 5. Find Median from Data Stream

### 6. Word Ladder

### 7. Basic Calculator

### 8. Maximum Profit in Job Scheduling

### 9. Merge k Sorted Lists

### 10. Largest Rectangle in Histogram