2024/9/3 Hot100 binaryTree 最后一题

src/main/java/com/cool/hot100/binary_tree/Num124.java

@@ -0,0 +1,31 @@
+package com.cool.hot100.binary_tree;
+
+/**
+ * Created with IntelliJ IDEA.
+ *
+ * @Author: Cool
+ * @Date: 2024/09/03/09:37
+ * DayNumber 1
+ * Hard 3
+ * Level ?
+ */
+public class Num124 {
+
+    int res = Integer.MIN_VALUE;
+
+    public int maxPathSum(TreeNode root) {
+        dfs(root);
+        return res;
+    }
+
+    public int dfs(TreeNode root) {
+        if (root == null) {
+            return 0;
+        }
+        int left = Math.max(0, dfs(root.left));
+        int right = Math.max(0, dfs(root.right));
+
+        res = Math.max(res, root.val + left + right);
+        return root.val + Math.max(left,right);
+    }
+}

src/main/java/com/cool/hot100/binary_tree/Num543.java

@@ -11,20 +11,21 @@ package com.cool.hot100.binary_tree;
  */
 public class Num543 {
 
-    int max=0;
+    int max = 0;
+
     public int diameterOfBinaryTree(TreeNode root) {
         if (root == null) return 0;
         int left = getTreeDeep(root.left);
         int right = getTreeDeep(root.right);
-        return Math.max(max,left+right);
+        return Math.max(max, left + right);
     }
 
     private int getTreeDeep(TreeNode root) {
         if (root == null) return 0;
         int left = getTreeDeep(root.left);
-        int right=getTreeDeep(root.right);
-        max = Math.max(max,left+right );
-        return Math.max(left,right)+1;
+        int right = getTreeDeep(root.right);
+        max = Math.max(max, left + right);
+        return Math.max(left, right) + 1;
     }
 
 }