import java.util.*;
import java.lang.*;
import java.io.*;

class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner in = new Scanner(System.in);
		String s = in.next();
		char[] s1 = s.toCharArray();
		char temp;
		for (int i=1;i<s.length();i+=2){
			temp=s.charAt(i-1);
			s1[i-1]=s.charAt(i);
			s1[i]=temp;
		}
		String s2 = String.valueOf(s1);
		System.out.println(s2);
		
	}
}