import java.util.*;


public class Main{
  
  public static void main(String[] args){
    ArrayList<String> array = new ArrayList<String>();
      
    Scanner scan = new Scanner(System.in);
    //int val = scan.nextInt();
    //System.out.print(val);
    //int val2 = scan.nextInt();
    //System.out.print(val2);
    while(scan.hasNext()){
      array.add(scan.next());
    }
    
    Collections.sort(array);
    
    String val=""; 
    for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    }
    
    System.out.print(val);
  }
   
} import java.util.*; util.* java public class Main{
  
  public static void main(String[] args){
    ArrayList<String> array = new ArrayList<String>();
      
    Scanner scan = new Scanner(System.in);
    //int val = scan.nextInt();
    //System.out.print(val);
    //int val2 = scan.nextInt();
    //System.out.print(val2);
    while(scan.hasNext()){
      array.add(scan.next());
    }
    
    Collections.sort(array);
    
    String val=""; 
    for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    }
    
    System.out.print(val);
  }
   
} Main public static void main(String[] args){
    ArrayList<String> array = new ArrayList<String>();
      
    Scanner scan = new Scanner(System.in);
    //int val = scan.nextInt();
    //System.out.print(val);
    //int val2 = scan.nextInt();
    //System.out.print(val2);
    while(scan.hasNext()){
      array.add(scan.next());
    }
    
    Collections.sort(array);
    
    String val=""; 
    for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    }
    
    System.out.print(val);
  } main {
    ArrayList<String> array = new ArrayList<String>();
      
    Scanner scan = new Scanner(System.in);
    //int val = scan.nextInt();
    //System.out.print(val);
    //int val2 = scan.nextInt();
    //System.out.print(val2);
    while(scan.hasNext()){
      array.add(scan.next());
    }
    
    Collections.sort(array);
    
    String val=""; 
    for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    }
    
    System.out.print(val);
  } ArrayList<String> array = new ArrayList<String>(); array new ArrayList<String>() Scanner scan = new Scanner(System.in); scan new Scanner(System.in) while(scan.hasNext()){
      array.add(scan.next());
    } scan.hasNext() scan.hasNext scan {
      array.add(scan.next());
    } array.add(scan.next()) array.add array scan.next() scan.next scan Collections.sort(array) Collections.sort Collections array String val=""; val "" for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    } int i=2; int i=2; i 2 i<array.size() i array.size() array.size array i++ i++ i {
      val = val + array.get(i);
    } {
      val = val + array.get(i);
    } val = val + array.get(i) val val + array.get(i) val array.get(i) array.get array i System.out.print(val) System.out.print System.out System System.out val String[] args args public class Main{
  
  public static void main(String[] args){
    ArrayList<String> array = new ArrayList<String>();
      
    Scanner scan = new Scanner(System.in);
    //int val = scan.nextInt();
    //System.out.print(val);
    //int val2 = scan.nextInt();
    //System.out.print(val2);
    while(scan.hasNext()){
      array.add(scan.next());
    }
    
    Collections.sort(array);
    
    String val=""; 
    for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    }
    
    System.out.print(val);
  }
   
} public class Main{
  
  public static void main(String[] args){
    ArrayList<String> array = new ArrayList<String>();
      
    Scanner scan = new Scanner(System.in);
    //int val = scan.nextInt();
    //System.out.print(val);
    //int val2 = scan.nextInt();
    //System.out.print(val2);
    while(scan.hasNext()){
      array.add(scan.next());
    }
    
    Collections.sort(array);
    
    String val=""; 
    for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    }
    
    System.out.print(val);
  }
   
} Main
import java.util.*;


public class Main{
  
  public static void main(String[] args){
    ArrayList<String> array = new ArrayList<String>();
      
    Scanner scan = new Scanner(System.in);
    //int val = scan.nextInt();
    //System.out.print(val);
    //int val2 = scan.nextInt();
    //System.out.print(val2);
    while(scan.hasNext()){
      array.add(scan.next());
    }
    
    Collections.sort(array);
    
    String val=""; 
    for(int i=2; i<array.size(); i++){
      val = val + array.get(i);
    }
    
    System.out.print(val);
  }
   
}