import java.util.*;

import java.io.*;

class Main {

public static String DashInsert(String str) {

char[] sayilar = str.toCharArray();

int oncekiSayi = Integer.parseInt(String.valueOf(sayilar[0]));

StringBuilder res = new StringBuilder(String.valueOf(oncekiSayi));

for (int i = 1; i < sayilar.length; i++) {

int sayi = Integer.parseInt(String.valueOf(sayilar[i]));

if (sayi != 0 && oncekiSayi % 2 == 1 && sayi % 2 == 1) {

res.append("-");

}

res.append(sayi);

oncekiSayi = sayi;

}

return res.toString();

}

public static void main(String[] args) {

// keep this function call here

Scanner s = new Scanner(System.in);

System.out.print(DashInsert(s.nextLine()));

}

}