solve problem Search In A Binary Search Tree

Author: P-ppc

README.md

@@ -203,6 +203,7 @@ All solutions will be accepted!
 |22|[Generate Parentheses](https://leetcode-cn.com/problems/generate-parentheses/description/)|[java/py/js](./algorithms/GenerateParentheses)|Easy|
 |704|[Binary Search](https://leetcode-cn.com/problems/binary-search/description/)|[java/py/js](./algorithms/BinarySearch)|Easy|
 |709|[To Lower Case](https://leetcode-cn.com/problems/to-lower-case/description/)|[java/py/js](./algorithms/ToLowerCase)|Easy|
+|700|[Search In A Binary Search Tree](https://leetcode-cn.com/problems/search-in-a-binary-search-tree/description/)|[java/py/js](SearchInABinarySearchTree)|Easy|
 
 # Database
 |#|Title|Solution|Difficulty|

algorithms/SearchInABinarySearchTree/README.md

@@ -0,0 +1,2 @@
+# Search In A Binary Search Tree
+This problem is easy to sovle by recursive

algorithms/SearchInABinarySearchTree/Solution.java

@@ -0,0 +1,16 @@
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    public TreeNode searchBST(TreeNode root, int val) {
+        if (root == null || root.val == val) return root;
+        else if (root.val > val) return searchBST(root.left, val);
+        else return searchBST(root.right, val);
+    }
+}

algorithms/SearchInABinarySearchTree/solution.js

@@ -0,0 +1,20 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val) {
+ *     this.val = val;
+ *     this.left = this.right = null;
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @param {number} val
+ * @return {TreeNode}
+ */
+var searchBST = function(root, val) {
+    // Should return null, but the acception is []
+    if (!root) return []
+    
+    if (root.val === val) return root
+    else if (root.val > val) return searchBST(root.left, val)
+    else return searchBST(root.right, val)
+};

algorithms/SearchInABinarySearchTree/solution.py

@@ -0,0 +1,23 @@
+# Definition for a binary tree node.
+# class TreeNode(object):
+#     def __init__(self, x):
+#         self.val = x
+#         self.left = None
+#         self.right = None
+
+class Solution(object):
+    def searchBST(self, root, val):
+        """
+        :type root: TreeNode
+        :type val: int
+        :rtype: TreeNode
+        """
+        if not root:
+            return None
+        
+        if root.val == val:
+            return root
+        elif root.val > val:
+            return self.searchBST(root.left, val)
+        else:
+            return self.searchBST(root.right, val)