add code of 235

Author: Li Li

LeetcodeCShaprDotNetCore/Program.cs

@@ -4,17 +4,6 @@ namespace LeetcodeCShaprDotNetCore {
     class Program {
         static void Main(string[] args) {
 
-
         }
     }
 }
-
-
-/*
-Given "abcabcbb", the answer is "abc", which the length is 3.
-
-Given "bbbbb", the answer is "b", with the length of 1.
-
-Given "pwwkew", the answer is "wke", with the length of 3. 
-Note that the answer must be a substring, "pwke" is a subsequence and not a substring.
- */

LeetcodeCShaprDotNetCore/Solution.cs

@@ -5,16 +5,14 @@
 
 namespace LeetcodeCShaprDotNetCore {
     public class Solution {
-        public TreeNode SortedArrayToBST(int[] nums) {
-            return SortedArrayToBST(nums, 0, nums.Length - 1);
-        }
-        private TreeNode SortedArrayToBST(int[] nums, int left, int right) {
-            if (nums == null || nums.Length == 0 || left > right) return null;
-            int mid = left + (right - left) / 2;
-            TreeNode root = new TreeNode(nums[mid]);
-            root.left = SortedArrayToBST(nums, left, mid - 1);
-            root.right = SortedArrayToBST(nums, mid + 1, right);
-            return root;
+        public TreeNode LowestCommonAncestor(TreeNode root, TreeNode p, TreeNode q) {
+            if (root.val > p.val && root.val > q.val) {
+                return LowestCommonAncestor(root.left, p, q);
+            } else if (root.val < p.val && root.val < q.val) {
+                return LowestCommonAncestor(root.right, p, q);
+            } else {
+                return root;
+            }
         }
     }
 }

README.md

@@ -3,7 +3,7 @@
 I will use this repository to make notes for leetcode solutions and classify the problems by different topics.
 
 ## Solved Problem List
-Total solved: 89
+Total solved: 90
 
 ### microsoft-labed
 ID | Difficulty | Tags | Solution | Similar Problem
@@ -12,6 +12,7 @@ ID | Difficulty | Tags | Solution | Similar Problem
 419 | Medium | Two dimentional array | [Battleships in a Board](https://github.com/kflili/LeetcodeCShaprDotNetCore/blob/master/top-interview-questions/419.%20Battleships%20in%20a%20Board.cs)
 273 | Hard | Math, string | [Integer to English Words](https://github.com/kflili/LeetcodeCShaprDotNetCore/blob/master/top-interview-questions/273.%20Integer%20to%20English%20Words.cs)
 54 | Medium | Array | [Spiral Matrix](https://github.com/kflili/LeetcodeCShaprDotNetCore/blob/master/top-interview-questions/54.%20Spiral%20Matrix.cs)
+235 | Medium | BST | [Lowest Common Ancestor of a Binary Search Tree](https://github.com/kflili/LeetcodeCShaprDotNetCore/blob/master/top-interview-questions/235.%20Lowest%20Common%20Ancestor%20of%20a%20Binary%20Search%20Tree.cs)
 
 
 ### top-interview-questions