add 654

Author: luliyucoordinate

Diff for: README.md

@@ -254,6 +254,7 @@ LeetCode
 |0560|[Subarray Sum Equals K](https://leetcode.com/problems/subarray-sum-equals-k/) | c | [c++](./src/0560-Subarray-Sum-Equals-K/0560.cpp) |[python](./src/0560-Subarray-Sum-Equals-K/0560.py)|||Medium|
 |0637|[Average of Levels in Binary Tree](https://leetcode.com/problems/subarray-sum-equals-k/) | c | [c++](./src/0637-Average-of-Levels-in-Binary-Tree/0637.cpp) |[python](./src/0637-Average-of-Levels-in-Binary-Tree/0637.py)|||Easy|
 |0652|[Find Duplicate Subtrees](https://leetcode.com/problems/find-duplicate-subtrees/) | c | [c++](./src/0652-Find-Duplicate-Subtrees/0652.cpp) |[python](./src/0652-Find-Duplicate-Subtrees/0652.py)|||Medium|
+|0654|[Maximum Binary Tree](https://leetcode.com/problems/maximum-binary-tree/) | c | [c++](./src/0654-Maximum-Binary-Tree/0654.cpp) |[python](./src/0654-Maximum-Binary-Tree/0654.py)|||Medium|
 |0684|[Redundant Connection](https://leetcode.com/problems/redundant-connection/) | c | [c++](./src/0684-Redundant-Connection/0684.cpp) |[python](./src/0684-Redundant-Connection/0684.py)|||Medium|
 |0687|[Longest Univalue Path](https://leetcode.com/problems/redundant-connection/) | c | [c++](./src/0687-Longest-Univalue-Path/0687.cpp) |[python](./src/0687-Longest-Univalue-Path/0687.py)|||Easy|
 |0739|[Daily Temperatures](https://leetcode.com/problems/daily-temperatures/) | c | [c++](./src/0739-Daily-Temperatures/0739.cpp) |[python](./src/0739-Daily-Temperatures/0739.py)|||Medium|

Diff for: src/0654-Maximum-Binary-Tree/0654.cpp

@@ -0,0 +1,25 @@
+static int x = []() {std::ios::sync_with_stdio(false); cin.tie(0); return 0; }();
+class Solution 
+{
+public:
+    TreeNode* constructMaximumBinaryTree(vector<int>& nums) 
+    {
+        vector<TreeNode*> stack;
+        for (int n : nums)
+        {
+            TreeNode* cur = new TreeNode(n);
+            while (!stack.empty() and (stack.back())->val < n)
+            {
+                cur->left = stack.back(), stack.pop_back();
+            }
+            
+            if (!stack.empty()) 
+            {
+                TreeNode* tmp = stack.back();
+                tmp->right = cur;
+            }
+            stack.push_back(cur);
+        }
+        return stack[0];
+    }
+};

Diff for: src/0654-Maximum-Binary-Tree/0654.py

@@ -0,0 +1,13 @@
+class Solution:
+    def constructMaximumBinaryTree(self, nums: List[int]) -> TreeNode:
+        stack = list()
+        for n in nums:
+            cur = TreeNode(n)
+            while stack and stack[-1].val < n:
+                cur.left = stack.pop()
+                
+            if stack:
+                stack[-1].right = cur
+            stack.append(cur)
+            
+        return stack[0]