2024/8/30 Hot100 binaryTree 昨日的题

src/main/java/com/cool/hot100/binary_tree/Num102.java

@@ -1,21 +1,45 @@
 package com.cool.hot100.binary_tree;
 
-import java.util.List;
+import java.util.*;
 
 /**
  * Created with IntelliJ IDEA.
  *
  * @Author: Cool
- * @Date: 2024/08/28/17:24
+ * @Date: 2024/08/29/17:24
  * DayNumber 4
  * Hard 2
  * Level ?
+ * @Description 昨日题今日做
+ * FinishTime: 2024/8/30/
  */
 public class Num102 {
 
 
     public List<List<Integer>> levelOrder(TreeNode root) {
+        List<List<Integer>> retList = new ArrayList<>();
+        if (root == null) {
+            return retList;
+        }
+        Queue<TreeNode> queue = new LinkedList<>();
+        queue.add(root);
+        while (!queue.isEmpty()) {
+            List<Integer> list=new ArrayList<>();
+            int size = queue.size();
+            for (int i = 0; i < size; i++) {
+                TreeNode head = queue.poll();
+                list.add(head.val);
+                if (head.left != null) {
+                    queue.add(head.left);
+                }
+                if (head.right != null) {
+                    queue.add(head.right);
+                }
+            }
+            retList.add(list);
 
+        }
+        return retList;
     }
 
 }

src/main/java/com/cool/one_question_per_day/LeetCode20240829.java

@@ -9,7 +9,7 @@ package com.cool.one_question_per_day;
  * Hard 1
  */
 public class LeetCode20240829 {
-    public boolean satisfiesConditions(int[][] grid) {
+//    public boolean satisfiesConditions(int[][] grid) {
-
+//
-    }
+//    }
 }