210. Course Schedule II
210. Course Schedule II
Check 207. Course Schedule
Classic
207. Course Schedule
207. Course Schedule
這一個題目的設計滿巧秒的，我個人覺得這個題目綜合了樹的遍歷（遞迴）、回溯法、動態規劃以及資料與圖形轉換的設計，外加上題目可以套用在各種現實生活問題中。所以整體而言
1676. Lowest Common Ancestor of a Binary Tree IV
1676. Lowest Common Ancestor of a Binary Tree IV
Check
1650. Lowest Common Ancestor of a Binary Tree III
1650. Lowest Common Ancestor of a Binary Tree III
Check
1644. Lowest Common Ancestor of a Binary Tree II
1644. Lowest Common Ancestor of a Binary Tree II
Check
236. Lowest Common Ancestor of a Binary Tree
236. Lowest Common Ancestor of a Binary Tree
Check 235.
235. Lowest Common Ancestor of a Binary Search Tree
* 235. Lowest Common Ancestor of a Binary Search Tree
* 236.
18. 4 Sum
18. 4 Sum
Check 15. 3 Sum
887. Super Egg Drop
887. Super Egg Drop
Check 1884-egg-drop-with-2-eggs-and-n-floors
5. Longest Palindromic Substring
5. Longest Palindromic Substring
這一題是我們要找出子字串中的最長的回文，其實最好從暴力解法開始學習起，前面的題目已經重複提過了好多次的回文的性質，這裡就用暴力法先來思考以下。
暴力法 (TLE)