From 4054d189d52a4e383b836088d9726c6547443945 Mon Sep 17 00:00:00 2001
From: Shawn <36914076+8kEatRadish@users.noreply.github.com>
Date: Fri, 2 Apr 2021 12:19:08 +0800
Subject: [PATCH] feat:add LeetCode337 java solution code.

---
 .../0300-0399/0337.House Robber III/README.md | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/solution/0300-0399/0337.House Robber III/README.md b/solution/0300-0399/0337.House Robber III/README.md
index b6410dbdaacfd..40f5fe5a8bab2 100644
--- a/solution/0300-0399/0337.House Robber III/README.md	
+++ b/solution/0300-0399/0337.House Robber III/README.md	
@@ -55,6 +55,33 @@
 <!-- 这里可写当前语言的特殊实现逻辑 -->
 
 ```java
+class Solution {
+    //这里f（o）表示选择o节点的最大权重和
+    //这里g（o）表示不选择o节点最大权重和
+
+    //f(o) = g(o.left) + g(o.right) 因为选择了o节点，他的两个子节点就不可以选择
+    //g(0) = Math.max(f(o.left),g(o.left)) + Math.max(f(o.right),g(o.right)) 不选择o节点，他的子节点可选择，也可不选择
+    Map<TreeNode, Integer> f = new HashMap<>();
+    Map<TreeNode, Integer> g = new HashMap<>();
+
+    public int rob(TreeNode root) {
+        dfs(root);
+        return Math.max(f.getOrDefault(root, 0), g.getOrDefault(root, 0));
+    }
+
+    private void dfs(TreeNode root) {
+        if (root == null) {
+            return;
+        }
+
+        dfs(root.left);
+        dfs(root.right);
+        
+        //选择了root，所以求和的时候要把root.val算进去
+        f.put(root, root.val + g.getOrDefault(root.left, 0) + g.getOrDefault(root.right, 0));
+        g.put(root, Math.max(f.getOrDefault(root.left, 0), g.getOrDefault(root.left, 0)) + Math.max(f.getOrDefault(root.right, 0), g.getOrDefault(root.right, 0)));
+    }
+}
 
 ```