#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
#include <cmath>
#include <cctype>
#include <cassert>
#include <vector>

using namespace std;

template <typename T> class tree
{ protected:

    struct node
    { T data;
      node * left, * right;

      node(T d, node * l = NULL, node * r = NULL)
      { data = d;
        left = l;
        right = r; } };

    void add(node * np, T x)
    { assert(np != NULL);
      while (true)
      { if (x < np->data)
          if (np->left == NULL)
          { np->left = new node(x);
            break; }
          else np = np->left;
        else
          if (np->right == NULL)
          { np->right = new node(x);
            break; }
          else
            np = np->right; } }

    bool find(node * np, T x)
    { while (true)
      { if (np == NULL)
          return false;
        if (np->data == x)
          return true;
        if (x < np->data)
          np = np->left;
        else
          np = np->right; } }
/*
      I have removed the definitions of
         void print(node * np, vector <T> & v)
      and
         void nsprint(node * np)
      because otherwise people would be lazy and just look at them.
      You need to be sure you can reconstruct them without help.
*/
    node * root;

  public:

    tree()
    { root = NULL; }

    void add(T x)
    { if (root == NULL)
        root = new node(x);
      else
        add(root, x); }

     bool find(T x)
     { return find(root, x); }
     
     void print(vector <T> & v)
     { print(root, v);
       cout << "\n"; }
     
     void msprint()
     { nsprint(root);
       cout << "\n"; } };

int main()
{ string s;
  tree <string> t;
  vector <string> data;
  while (true)
  { cin >> s;
    if (cin.fail())
      break;
    data.push_back(s); }

  for (string x: data)
    t.add(x);

  data.clear();
  t.print(data);

  for (string x: data)
    cout << x << " ";
  
  cout << "\n"; }