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

int main()
{
    string S;
    cin >> S;
    
    deque<char> dq;
    for(int i = 0; i < S.size(); i++)
    {
        if(dq.size() == 0) dq.push_back(S.at(i));
        else
        {
            if(dq.back() != S.at(i)) dq.push_back(S.at(i));
        }
    }
    
    while(!dq.empty())
    {
        cout << dq.front();
        dq.pop_front();
    }
    cout << endl;
    return 0;
}