refactor 655

fishercoder1534 · fishercoder1534 · commit ebaf44352fcd · 2019-08-30T07:23:34.000-07:00
diff --git a/src/main/java/com/fishercoder/solutions/_655.java b/src/main/java/com/fishercoder/solutions/_655.java
@@ -64,39 +64,42 @@
  */
 public class _655 {
 
-    /**
-     * Reference: https://discuss.leetcode.com/topic/98381/java-recursive-solution
-     * and https://leetcode.com/articles/print-binary-tree/
-     */
-    public List<List<String>> printTree(TreeNode root) {
-        List<List<String>> result = new LinkedList<>();
-        int height = root == null ? 1 : getHeight(root);
-        int rows = height;
-        int columns = (int) (Math.pow(2, height) - 1);
-        List<String> row = new ArrayList<>();
-        for (int i = 0; i < columns; i++) {
-            row.add("");
-        }
-        for (int i = 0; i < rows; i++) {
-            result.add(new ArrayList<>(row));
+    public static class Solution1 {
+
+        /**
+         * Reference: https://discuss.leetcode.com/topic/98381/java-recursive-solution
+         * and https://leetcode.com/articles/print-binary-tree/
+         */
+        public List<List<String>> printTree(TreeNode root) {
+            List<List<String>> result = new LinkedList<>();
+            int height = root == null ? 1 : getHeight(root);
+            int rows = height;
+            int columns = (int) (Math.pow(2, height) - 1);
+            List<String> row = new ArrayList<>();
+            for (int i = 0; i < columns; i++) {
+                row.add("");
+            }
+            for (int i = 0; i < rows; i++) {
+                result.add(new ArrayList<>(row));
+            }
+            populateResult(root, result, 0, rows, 0, columns - 1);
+            return result;
         }
-        populateResult(root, result, 0, rows, 0, columns - 1);
-        return result;
-    }
 
-    private void populateResult(TreeNode root, List<List<String>> result, int row, int totalRows, int i, int j) {
-        if (row == totalRows || root == null) {
-            return;
+        private void populateResult(TreeNode root, List<List<String>> result, int row, int totalRows, int i, int j) {
+            if (row == totalRows || root == null) {
+                return;
+            }
+            result.get(row).set((i + j) / 2, Integer.toString(root.val));
+            populateResult(root.left, result, row + 1, totalRows, i, (i + j) / 2 - 1);
+            populateResult(root.right, result, row + 1, totalRows, (i + j) / 2 + 1, j);
         }
-        result.get(row).set((i + j) / 2, Integer.toString(root.val));
-        populateResult(root.left, result, row + 1, totalRows, i, (i + j) / 2 - 1);
-        populateResult(root.right, result, row + 1, totalRows, (i + j) / 2 + 1, j);
-    }
 
-    private int getHeight(TreeNode root) {
-        if (root == null) {
-            return 0;
+        private int getHeight(TreeNode root) {
+            if (root == null) {
+                return 0;
+            }
+            return 1 + Math.max(getHeight(root.left), getHeight(root.right));
         }
-        return 1 + Math.max(getHeight(root.left), getHeight(root.right));
     }
 }
diff --git a/src/test/java/com/fishercoder/_655Test.java b/src/test/java/com/fishercoder/_655Test.java
@@ -16,11 +16,11 @@
 public class _655Test {
     private static List<List<String>> expected;
     private static TreeNode root;
-    private static _655 test;
+    private static _655.Solution1 solution1;
 
     @BeforeClass
     public static void setup() {
-        test = new _655();
+        solution1 = new _655.Solution1();
     }
 
     @Test
@@ -38,21 +38,21 @@ public void test1() {
         row2.add("");
         expected.add(row2);
         CommonUtils.printListList(expected);
-        assertEquals(expected, test.printTree(root));
+        assertEquals(expected, solution1.printTree(root));
     }
 
     @Test
     public void test2() {
         root = TreeUtils.constructBinaryTree(Arrays.asList(1, 2, 3, null, 4));
         TreeUtils.printBinaryTree(root);
-        CommonUtils.printListList(test.printTree(root));
+        CommonUtils.printListList(solution1.printTree(root));
     }
 
     @Test
     public void test3() {
         root = TreeUtils.constructBinaryTree(Arrays.asList(3, null, 30, 10, null, null, 15, null, 45));
         TreeUtils.printBinaryTree(root);
-        CommonUtils.printListList(test.printTree(root));
-        System.out.println(test.printTree(root));
+        CommonUtils.printListList(solution1.printTree(root));
+        System.out.println(solution1.printTree(root));
     }
 }
