solve problem Insert Into A Binary Search Tree

Author: P-ppc

README.md

@@ -305,6 +305,7 @@ All solutions will be accepted!
 |921|[Minimum Add To Make Parentheses Valid](https://leetcode-cn.com/problems/minimum-add-to-make-parentheses-valid/description/)|[java/py/js](./algorithms/MinimumAddToMakeParenthesesValid)|Medium|
 |797|[All Paths From Source To Target](https://leetcode-cn.com/problems/all-paths-from-source-to-target/description/)|[java/py/js](./algorithms/AllPathsFromSourceToTarget)|Medium|
 |789|[Escape The Ghosts](https://leetcode-cn.com/problems/escape-the-ghosts/description/)|[java/py/js](./algorithms/EscapeTheGhosts)|Medium|
+|701|[Insert Into A Binary Search Tree](https://leetcode-cn.com/problems/insert-into-a-binary-search-tree/description/)|[java/py/js](./algorithms/InsertIntoABinarySearchTree)|Medium|
 
 # Database
 |#|Title|Solution|Difficulty|

algorithms/InsertIntoABinarySearchTree/README.md

@@ -0,0 +1,2 @@
+# Insert Into A Binary Search Tree
+This problem is easy to solve

algorithms/InsertIntoABinarySearchTree/Solution.java

@@ -0,0 +1,33 @@
+/**
+ * Definition for a binary tree node.
+ * public class TreeNode {
+ *     int val;
+ *     TreeNode left;
+ *     TreeNode right;
+ *     TreeNode(int x) { val = x; }
+ * }
+ */
+class Solution {
+    public TreeNode insertIntoBST(TreeNode root, int val) {
+        if (root == null)
+            return new TreeNode(val);
+        
+        TreeNode p = root,
+                 pre = null;
+        
+        while (p != null) {
+            pre = p;
+            if (val < p.val)
+                p = p.left;
+            else
+                p = p.right;
+        }
+        
+        if (val < pre.val)
+            pre.left = new TreeNode(val);
+        else
+            pre.right = new TreeNode(val);
+
+        return root;
+    }
+}

algorithms/InsertIntoABinarySearchTree/solution.js

@@ -0,0 +1,34 @@
+/**
+ * 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 insertIntoBST = function(root, val) {
+    if (!root)
+        return new TreeNode(val)
+    
+    let p = root,
+        pre = null
+    
+    while (p) {
+        pre = p
+        if (val < p.val)
+            p = p.left
+        else
+            p = p.right
+    }
+    
+    if (val < pre.val)
+        pre.left = new TreeNode(val)
+    else
+        pre.right = new TreeNode(val)
+    
+    return root
+};

algorithms/InsertIntoABinarySearchTree/solution.py

@@ -0,0 +1,32 @@
+# 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 insertIntoBST(self, root, val):
+        """
+        :type root: TreeNode
+        :type val: int
+        :rtype: TreeNode
+        """
+        if not root:
+            return TreeNode(val)
+        
+        p = root
+        pre = root
+        while p:
+            pre = p
+            if val < p.val:
+                p = p.left
+            else:
+                p = p.right
+        
+        if val < pre.val:
+            pre.left = TreeNode(val)
+        else:
+            pre.right = TreeNode(val)
+
+        return root