add java solution for Problem 701 (doocs#205)

Merged doocs#205

Author: ashmichheda

solution/0701.Insert into a Binary Search Tree/Solution.java

@@ -0,0 +1,27 @@
+/**
+ * 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){
+            root = new TreeNode(val);
+      }
+
+        if(val < root.val){
+            root.left = insertIntoBST(root.left, val);
+        }
+        else if(val > root.val){
+            root.right = insertIntoBST(root.right, val);
+        }
+
+        // return the unchanged pointer
+        return root;
+    }
+}

solution/README.md

@@ -999,6 +999,7 @@
 ├── 0701.Insert into a Binary Search Tree
 │   ├── README.md
 │   └── Solution.py
+│   └── Solution.java
 ├── 0703.Kth Largest Element in a Stream
 │   ├── README.md
 │   └── Solution.java