class Solution { public: TreeNode* constructMaximumBinaryTree(vector<int>& nums) { if (nums.size() == 0) return NULL; else if (nums.size() == 1) { TreeNode * node = new TreeNode(nums[0]); return node; } else { int max = 0; for (int i = 0; i<nums.size(); i++) { if (nums[i]>nums[max]) max = i; } vector<int> left_num, right_num; for (int i = 0; i<max; i++) { left_num.push_back(nums[i]); } for (int j = max + 1; j<nums.size(); j++) { right_num.push_back(nums[j]); } TreeNode * node = new TreeNode(nums[max]); node->left = constructMaximumBinaryTree(left_num); node->right = constructMaximumBinaryTree(right_num); return node; } } };