level

Author: yubinbai

src/levelOrder/Solution.java

@@ -1,45 +1,45 @@
 import java.util.*;
 
 class TreeNode {
-    int val;
-    TreeNode left;
-    TreeNode right;
-    TreeNode(int x) {
-        val = x;
-    }
+  int val;
+  TreeNode left;
+  TreeNode right;
+  TreeNode(int x) {
+    val = x;
+  }
 }
 
 public class Solution {
 
-    public ArrayList<ArrayList<Integer>> levelOrder(TreeNode root) {
-        ArrayList<ArrayList<Integer>> ret = new ArrayList<ArrayList<Integer>>();
-        if (root == null) return ret;
+  public ArrayList<ArrayList<Integer>> levelOrder(TreeNode root) {
+    ArrayList<ArrayList<Integer>> ret = new ArrayList<ArrayList<Integer>>();
+    if (root == null) return ret;
 
-        ArrayList<TreeNode> currLevel, nextLevel;
-        currLevel = new ArrayList<TreeNode>();
-        currLevel.add(root);
+    ArrayList<TreeNode> currLevel, nextLevel;
+    currLevel = new ArrayList<TreeNode>();
+    currLevel.add(root);
 
-        while (!currLevel.isEmpty()) {
-            nextLevel = new ArrayList<TreeNode>();
-            ArrayList<Integer> intList = new ArrayList<Integer>();
-            for (TreeNode e : currLevel) {
-                intList.add(e.val);
-                if (e.left != null) nextLevel.add(e.left);
-                if (e.right != null) nextLevel.add(e.right);
-            }
+    while (!currLevel.isEmpty()) {
+      nextLevel = new ArrayList<TreeNode>();
+      ArrayList<Integer> intList = new ArrayList<Integer>();
+      for (TreeNode e : currLevel) {
+        intList.add(e.val);
+        if (e.left != null) nextLevel.add(e.left);
+        if (e.right != null) nextLevel.add(e.right);
+      }
 
-            ret.add(intList);
-            currLevel = nextLevel;
-        }
-        return ret;
+      ret.add(intList);
+      currLevel = nextLevel;
     }
+    return ret;
+  }
 
-    public static void main(String[] args) {
-        Solution sol = new Solution();
-        TreeNode t = new TreeNode(1);
-        t.left = new TreeNode(2);
-        t.right = new TreeNode(44);
-        t.left.left = new TreeNode(3);
-        System.out.println(sol.levelOrder(t));
-    }
+  public static void main(String[] args) {
+    Solution sol = new Solution();
+    TreeNode t = new TreeNode(1);
+    t.left = new TreeNode(2);
+    t.right = new TreeNode(44);
+    t.left.left = new TreeNode(3);
+    System.out.println(sol.levelOrder(t));
+  }
 }

src/levelOrder/Solution.js

@@ -0,0 +1,31 @@
+/* class TreeNode {
+ *   int val;
+ *   TreeNode left;
+ *   TreeNode right;
+ * }
+ */
+
+function levelOrder(root) {
+  let ret = [];
+  if (root == null) {
+    return ret;
+  }
+  let currLevel = [root];
+  let nextLevel = [];
+  while (currLevel.length > 0) {
+    nextLevel = [];
+    let intList = [];
+    for (let e of currLevel) {
+      intList.push(e.val);
+      if (e.left != null) {
+        nextLevel.push(e.left);
+      }
+      if (e.right != null) {
+        nextLevel.push(e.right);
+      }
+    }
+    ret.push(...intList);
+    currLevel = nextLevel;
+  }
+  return ret;
+}