Refactor custom DS solutions

Author: andrewbayd

src/com/andrewbayd/binarySearchTreeLCA/Solution.java renamed to src/com/andrewbayd/BinarySearchTreeLCA.java

@@ -1,12 +1,14 @@
-package com.andrewbayd.binarySearchTreeLCA;
+package com.andrewbayd;
+
+import com.andrewbayd.datastructures.TreeNode;
 
 /*
 Given a binary search tree (BST), find the lowest common ancestor (LCA) of two given nodes in the BST.
 
 https://leetcode.com/problems/lowest-common-ancestor-of-a-binary-search-tree/
  */
 
-public class Solution {
+public class BinarySearchTreeLCA {
 
     public TreeNode lowestCommonAncestorIterative(TreeNode root, TreeNode p, TreeNode q) {
         while (root != null) {

src/com/andrewbayd/binaryTreeInOrderTraversal/Solution.java renamed to src/com/andrewbayd/BinaryTreeInOrderTraversal.java

@@ -9,7 +9,7 @@
 https://leetcode.com/problems/binary-tree-inorder-traversal/
  */
 
-public class Solution {
+public class BinaryTreeInOrderTraversal {
     public List<Integer> inorderTraversal(TreeNode root) {
         List<Integer> result = new ArrayList<>();
         traversalRecursive(root, result);

src/com/andrewbayd/invertBinaryTree/Solution.java renamed to src/com/andrewbayd/InvertBinaryTree.java

@@ -1,12 +1,14 @@
-package com.andrewbayd.invertBinaryTree;
+package com.andrewbayd;
+
+import com.andrewbayd.datastructures.TreeNode;
 
 /*
 Given the root of a binary tree, invert the tree, and return its root.
 
 https://leetcode.com/problems/invert-binary-tree/
  */
 
-public class Solution {
+public class InvertBinaryTree {
 
     public TreeNode invertTree(TreeNode root) {
         invertRecursive(root);

src/com/andrewbayd/MergeTwoSortedLists.java

@@ -2,6 +2,13 @@
 
 import com.andrewbayd.datastructures.ListNode;
 
+/*
+Merge the two sorted lists in a one sorted list. The list should be made by splicing together the nodes of the first two lists.
+Return the head of the merged linked list.
+
+https://leetcode.com/problems/merge-two-sorted-lists/
+ */
+
 public class MergeTwoSortedLists {
     public static ListNode mergeTwoLists(ListNode list1, ListNode list2) {
         if (list1 == null) return list2;

src/com/andrewbayd/symmetricTree/Solution.java renamed to src/com/andrewbayd/SymmetricTree.java

@@ -1,12 +1,14 @@
-package com.andrewbayd.symmetricTree;
+package com.andrewbayd;
+
+import com.andrewbayd.datastructures.TreeNode;
 
 /*
 Given the root of a binary tree, check whether it is a mirror of itself (i.e., symmetric around its center).
 
 https://leetcode.com/problems/symmetric-tree/
  */
 
-public class Solution {
+public class SymmetricTree {
     public boolean isSymmetric(TreeNode root) {
         return isSymetricRecursive(root.left, root.right);
     }

src/com/andrewbayd/binarySearchTreeLCA/TreeNode.java

@@ -1,10 +1,10 @@
-package com.andrewbayd.invertBinaryTree;
+package com.andrewbayd.datastructures;
 
 // Definition for a binary tree node.
 public class TreeNode {
-    int val;
-    TreeNode left;
-    TreeNode right;
+    public int val;
+    public TreeNode left;
+    public TreeNode right;
 
     TreeNode() {
     }