The following code example is taken from the book
C++17 - The Complete Guide
by Nicolai M. Josuttis,
Leanpub, 2017
The code is licensed under a
Creative Commons Attribution 4.0 International License.
// raw code
#include "incomplete.hpp"
#include <iostream>
int main()
{
// create node tree:
Node root{"top"};
root.add(Node{"elem1"});
root.add(Node{"elem2"});
root[0].add(Node{"elem1.1"});
// print node tree:
root.print();
}