text: //
  // Created by andrew on 2021/5/29.
  //
  #include <iostream>
  #include <list>
  #include <future>
  #include <mutex>
  #include <thread>
  
  #include <shared_mutex>
  
  using namespace std;
  
  
  int main(int argc, char* argv[]) {
  
      // 看着图就可以手上写一个二叉树
      struct treenode {
          char const* name;
          treenode* left;
          treenode* right;
      } tree[] = {
              { "D", &tree[1], &tree[2] },
              { "B", &tree[3], &tree[4] },
              { "F", &tree[5], nullptr },
              { "A", nullptr, nullptr },
              { "C", nullptr, nullptr },
              { "E", nullptr, nullptr },
      };
  
      cout << tree->name << tree->left->name << endl;
  
      std::string name;
      name.reserve(200);
      name.shrink_to_fit();
  
  
  
  
      return 0;
  }
  