refactor 103

fishercoder1534 · fishercoder1534 · commit 1d2c80cab87f · 2018-03-16T08:09:27.000-07:00
diff --git a/src/main/java/com/fishercoder/solutions/_103.java b/src/main/java/com/fishercoder/solutions/_103.java
@@ -8,10 +8,9 @@
 import java.util.List;
 import java.util.Queue;
 
-
 /**
- * 103. Binary Tree Zigzag Level Order Traversal  
- * 
+ * 103. Binary Tree Zigzag Level Order Traversal
+ *
 Given a binary tree, return the zigzag level order traversal of its nodes' values.
  (ie, from left to right, then right to left for the next level and alternate between).
 
@@ -30,36 +29,38 @@
 ]
 */
 public class _103 {
-    public List<List<Integer>> zigzagLevelOrder(TreeNode root) {
-        Queue<TreeNode> q = new LinkedList();
-        List<List<Integer>> levels = new ArrayList();
-        if (root == null) {
-            return levels;
-        }
-        q.offer(root);
-        boolean forward = true;
-        while (!q.isEmpty()) {
-            int size = q.size();
-            List<Integer> level = new ArrayList();
-            for (int i = 0; i < size; i++) {
-                TreeNode curr = q.poll();
-                level.add(curr.val);
-                if (curr.left != null) {
-                    q.offer(curr.left);
+    public static class Solution1 {
+        public List<List<Integer>> zigzagLevelOrder(TreeNode root) {
+            Queue<TreeNode> q = new LinkedList();
+            List<List<Integer>> levels = new ArrayList();
+            if (root == null) {
+                return levels;
+            }
+            q.offer(root);
+            boolean forward = true;
+            while (!q.isEmpty()) {
+                int size = q.size();
+                List<Integer> level = new ArrayList();
+                for (int i = 0; i < size; i++) {
+                    TreeNode curr = q.poll();
+                    level.add(curr.val);
+                    if (curr.left != null) {
+                        q.offer(curr.left);
+                    }
+                    if (curr.right != null) {
+                        q.offer(curr.right);
+                    }
                 }
-                if (curr.right != null) {
-                    q.offer(curr.right);
+                if (forward) {
+                    forward = false;
+                    levels.add(level);
+                } else {
+                    Collections.reverse(level);
+                    levels.add(level);
+                    forward = true;
                 }
             }
-            if (forward) {
-                forward = false;
-                levels.add(level);
-            } else {
-                Collections.reverse(level);
-                levels.add(level);
-                forward = true;
-            }
+            return levels;
         }
-        return levels;
     }
 }
