using System; using static System.Console; using System.Linq; using System.Collections.Generic; class Program { static int NN => int.Parse(ReadLine()); static int[] NList => ReadLine().Split().Select(int.Parse).ToArray(); static int[][] NArr(long n) => Enumerable.Repeat(0, (int)n).Select(_ => NList).ToArray(); public static void Main() { Solve(); } static void Solve() { var s = ReadLine(); var ans = new List(); for (var i = 0; i < s.Length; ++i) { if (i + 1 == s.Length || s[i] != s[i + 1]) ans.Add(s[i]); } WriteLine(string.Concat(ans)); } }