@@ -0,0 +1,1183 @@
+package com.fishercoder;%0A%0Aimport com.fishercoder.common.classes.TreeNode;%0Aimport com.fishercoder.common.utils.CommonUtils;%0Aimport com.fishercoder.common.utils.TreeUtils;%0Aimport com.fishercoder.solutions._144;%0Aimport org.junit.BeforeClass;%0Aimport org.junit.Test;%0A%0Aimport java.util.Arrays;%0Aimport java.util.List;%0A%0Apublic class _144Test %7B%0A    private static _144.Solution1 solution1;%0A    private static _144.Solution2 solution2;%0A    private static TreeNode root;%0A    private static List%3CInteger%3E inorder;%0A%0A    @BeforeClass%0A    public static void setup() %7B%0A        solution1 = new _144.Solution1();%0A        solution2 = new _144.Solution2();%0A    %7D%0A%0A    @Test%0A    public void test1() %7B%0A        root = TreeUtils.constructBinaryTree(Arrays.asList(3, 1, null, null, 5, 2, null, null, 4));%0A        inorder = solution1.preorderTraversal(root);%0A        CommonUtils.printList(inorder);%0A    %7D%0A%0A    @Test%0A    public void test2() %7B%0A        root = TreeUtils.constructBinaryTree(Arrays.asList(1, 2, 3, 4, null, 5, 6, null, 7, null, null, null, null, 8, 9));%0A        TreeUtils.printBinaryTree(root);%0A        inorder = solution1.preorderTraversal(root);%0A        CommonUtils.printList(inorder);%0A    %7D%0A%0A%7D%0A

refactor 144