#include <bits/stdc++.h>
#include <string>
using namespace std;

/*
 * Complete the 'superReducedString' function below.
 *
 * The function is expected to return a STRING.
 * The function accepts STRING s as parameter.
 */

string superReducedString(string s) {
    for(int i=1;i<s.length();i++){
        if(s[i]==s[i-1]){
            s.erase(s.begin()+i);
            s.erase((s.begin()+(i-1)));
        i=1;
            
        }
        if(s.length()==0){
            return "Empty String";
        }
        
    }
    if(s[0]==s[1]){
        return "Empty String";
    }
    return s;
}

int main()
{
    ofstream fout(getenv("OUTPUT_PATH"));

    string s;
    getline(cin, s);

    string result = superReducedString(s);

    fout << result << "\n";

    fout.close();

    return 0;
}