讓我們用 Javascript 寫一個數獨求解器！

Sudoku is a very fun exercise that you can get lost in for hours!
In this class we'll cover how to write a Sudoku application, and then we'll implement an algorithm called "backtracking with constraint propagation" that can solve all valid Sudoku puzzles in milliseconds!
We'll also cover strategies that students can use to solve real puzzles by hand, away from the computer.

Each class will start with a short lecture and then we will all write code in our own editors on repl.it. Students will be given a Repl.it starter, and we will code together each step of the way. As we develop the code, I will help learners tackle coding issues. 

I will teach modern Javascript features and key computer science problem-solving concepts. Students will gain working experience with computer programming, including developing solutions and debugging code to produce a working application.

Pre-requisites:
• Learners should know basic javascript: variables, for loops, and objects.
• More modern Javascript notation like `for in loops`, template strings are optional but helpful. We will cover and gain experience with these.

Lesson breakdown:
Lesson 1: Introduce repl.it and we implement the rules of sudoku
Lesson 2: We learn about sudoku solving strategies, and implement two simple ones that solve easy puzzles
Lesson 3: We implement backtracking search to solve all puzzles
Lesson 4: We look at the speed of our approach, go a bit more into the theory of backtracking search and other similar AI algorithms. We look at other ways to solve sudoku, as well as possible improvements to the app they've made.