Add unit test notes

Author: o-p

README.md

@@ -1,3 +1,25 @@
 # 我要刷 LeetCode
 
 第一階段先以這個 list 為目標: [Blind Curated 75](https://leetcode.com/list/xoqag3yj/)
+
+## Unit Tests
+
+各種語言與執行環境的測試方法:
+
+* TypeScript (Node.js + Jest)
+
+  ```bash
+  $ yarn test problems/
+  ```
+
+* TypeScript (Deno)
+
+  ```bash
+  $ deno test problems/*/*.test.deno.ts
+  ```
+  
+* Go
+
+  ```bash
+  go test -v ./problems/...
+  ```