import java.util.*;

/**
 * Created by Justin on 11/23/17.
 */
public class Driver1 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        HashMap<String, ArrayList<String>> h1 = new HashMap<>();

        boolean b = true;
        while(b) {
            String s = sc.nextLine();
            if(!s.equals("")) {
                String[] s1 = s.split(" -> ");
                String s2 = s1[1];
                String[] s3 = s2.split(",");
                ArrayList<String> a1 = new ArrayList<>();
                for(String s4 : s3) {
                    a1.add(s4);
                }
                h1.put(s1[0], a1);
            }
            else {
                b = false;
            }
        }
        String printThis = "";
        String s = path(h1);
        //System.out.println("hitting this");
        String[] s1 = s.split("->");
        for(int i = 0; i < s1.length; i++) {
            if(i==0) {
                printThis += s1[i];
            }
            else {
                printThis += s1[i].substring(s1[i].length() - 1, s1[i].length());
            }
        }
        System.out.println(printThis);
    }

    static String path(HashMap<String, ArrayList<String>> h1) {
        HashMap<String,Integer> h2 = new HashMap<>();

        Set<String> s1 = h1.keySet();
        Iterator itr = s1.iterator();
        while(itr.hasNext()) {
            String key = (String) itr.next();
            ArrayList<String> temp = h1.get(key);
            for(String i : temp) {
                h2.put(i,0);
            }
            h2.put(key,0);
        }

        //System.out.println(h2.toString());

        Set<String> s2 = h1.keySet();
        Iterator itr1 = s2.iterator();
        while(itr1.hasNext()) {
            String key = (String) itr1.next();
            //System.out.println("key: " + key);
            int change = h2.get(key);
            ArrayList<String> temp = h1.get(key);
            //System.out.println("Value: " + temp.toString());
            h2.replace(key,change+(temp.size()*-1));
            for(String i : temp) {
                int change2 = h2.get(i);
                h2.replace(i,change2+1);
            }

        }

        Set<String> s3 = h2.keySet();
        Iterator itr2 = s3.iterator();
        String start = "";
        String end = "";
        while(itr2.hasNext()) {
            String key = (String)itr2.next();
            if(h2.get(key) < 0) {
                end = key;
            }
            else if(h2.get(key) > 0) {
                start = key;
            }
        }

        ArrayList<String> addThis;
        if (h1.containsKey(start)) {
            addThis = h1.get(start);
        }
        else {
            addThis = new ArrayList<>();
        }
        addThis.add(end);
        h1.put(start,addThis);

        //System.out.println(start + " " + end);
        //System.out.println();
        //System.out.println(end);
        //System.out.println(start);
        ArrayList<String> xd = giveCycle(h1);
        xd.remove(xd.size() - 1);
        while(!(xd.get(xd.size()-1).equals(start)) || !(xd.get(0).equals(end))) {
            xd.add(0,xd.remove(xd.size()-1));
        }

        String pThis = "";
        for(String s : xd) {
            String add = s + "";
            pThis += add + "->";
        }

        return pThis.substring(0,pThis.length()-2);

    }

    static ArrayList<String> giveCycle(HashMap<String, ArrayList<String>> h1) {
        Set<String> s1 = h1.keySet();
        Iterator itr = s1.iterator();
        ArrayList<String> a1 = new ArrayList<>();
        //int counter = 1;
        String addThis = (String)itr.next();
        a1.add(addThis);
        a1.add(h1.get(addThis).get(0));
        if(h1.get(addThis).size() == 1) {
            h1.remove(addThis);
        }
        else {
            ArrayList<String> temp = h1.get(addThis);
            temp.remove(0);
            h1.replace(addThis,temp);
        }
        while(!h1.isEmpty()) {
            //System.out.println("hitthis3");
            if (h1.containsKey(a1.get(a1.size()-1))) {
                //System.out.println("hitthis1");
                String key = a1.get(a1.size()-1);
                String addPls = h1.get(a1.get(a1.size()-1)).get(0);
                a1.add(addPls);
                if(h1.get(key).size() == 1) {
                    h1.remove(key);
                }
                else {
                    ArrayList<String> temp = h1.get(key);
                    temp.remove(0);
                    h1.replace(key,temp);
                }
            }
            else {
                //System.out.println("hitthis2");
                int saveNum = 0;
                //int cur = 0;
                ArrayList<String> replace = new ArrayList<>();
                for(int i = 0; i < a1.size(); i++) {
                    if(h1.containsKey(a1.get(i))) {
                        saveNum = i;
                        //cur = a1.get(i);
                        break;
                    }
                }
                for(int j = saveNum; j < a1.size(); j++) {
                    replace.add(a1.get(j));
                }
                for(int k = 1; k <= saveNum; k++) {
                    replace.add(a1.get(k));
                }
                a1 = replace;
            }

            //System.out.println(a1.toString());
        }
        //System.out.println("hitthis4");
        return a1;
    }

}