#include <memory>
#include <string>
#include <iostream>
 
using namespace std;
 
static size_t indent = 0;
 
struct Base
{
  int value;
 
  Base(int value) : value(value) { }
  ~Base() {
    cout << string(indent*2, ' ') << "base destructor for " << value << endl;
    --indent;
  }
};
 
struct Node : public Base
{
  std::unique_ptr<Node> next;
 
  Node(int value, Node* next) : Base(value), next(next) { }
 
  ~Node()
  {
    ++indent;
    cout << string(indent*2, ' ') << "started destruction of " << value << endl;
  }
};
 
int main()
{
  Node* node = new Node(0, nullptr);
  for (int i = 1; i <= 5; ++i)
    node = new Node(i, node);
 
  delete node;
 
  return 0;
}

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