#include <bits/stdc++.h>
using namespace std;
int f[200005];
int main() {
  string str;
  cin >> str;
  f[0] = 1;
  for (int i = 1; i < str.length(); i++) {
    if (str[i] == str[i - 1])
      f[i] = f[i - 1] + 1;
    else
      f[i] = 1;
  }
  int last = 0, plast = 0;
  cout << str[0];
  for (int i = 1; i < str.length(); i++) {
    if (f[i] == 1) {
      cout << str[i];
      plast = last;
      last = i;
    }
    if (f[i] == 2 && f[plast] == 1) {
      cout << str[i];
      plast = last;
      last = i;
    }
  }
  puts("");
}
