#include <iostream>
#include <iomanip>
#include <string>
#include <vector>

using namespace std;

class node
{ protected:
    string data;
    vector <node *> child;

  public:
    node(string d)
    { data = d; }

    node * add(node * p)
    { child.push_back(p);
      return this; }

    string get_data()
    { return data; }

    int get_num_children()
    { return child.size(); }

    node * get_child(int i)
    { return child[i]; }
};

node * mn(string s)
{ return new node(s); }

bool print(node * p, int wanted_depth, int actual_depth)
{ if (wanted_depth == actual_depth)
  { cout << setw(actual_depth * 5) << "" << p->get_data() << "\n";
    return p->get_num_children() > 0; }
  bool any_children = false;
  int num = p->get_num_children();
  int i = 0;
  while (i < num)
  { bool any_children_here = print(p->get_child(i), wanted_depth, actual_depth + 1);
    any_children = any_children || any_children_here;
    i += 1; }
  return any_children; }

void print(node * p)
{ for (int wanted = 1; true; wanted += 1)
    if (! print(p, wanted, 1))
      break; }
    
int main()
{ node * t = mn("ant")
                      ->add(mn("bat")
                                     ->add(mn("egg")
                                                    ->add(mn("kit"))
                                                    ->add(mn("log")))
                                     ->add(mn("fig"))
                                     ->add(mn("git")
                                                    ->add(mn("map"))
                                                    ->add(mn("nut"))
                                                    ->add(mn("old"))
                                                    ->add(mn("pig"))))
                      ->add(mn("cat")
                                     ->add(mn("hat")))
                      ->add(mn("dog")
                                     ->add(mn("ink")
                                                    ->add(mn("qat"))
                                                    ->add(mn("rat")))
                                     ->add(mn("jug")
                                                    ->add(mn("sud"))
                                                    ->add(mn("tip"))));
  print(t); }