#include <iostream>
#include <string>
using namespace std;

int main(){
  string S;
  cin>>S;
  if(S.size()<2){
    cout<<S<<endl;
    return 0;
  }
  for(int i=S.size()-2;i>=0;i--){
    if(S.at(i)==S.at(i+1)){
      S.erase(i+1,1);
    }
  }
  cout<<S<<endl;
  return 0;
}