import java.util.Scanner;
public class Main{
public static void main(String[] args){
Scanner in=new Scanner(System.in);
int a=in.nextInt();
int b=a/1%10;
String f=String.valueOf(b);
int c=a/10%10;
String g=String.valueOf(c);
int d=a/100%10;
String h=String.valueOf(d);
int e=a/1000%10;
String i=String.valueOf(e);
System.out.println(f+g+h+i);
}
}