using System.Linq;

public class Program

{

    // Convert string to list GraphemeClusters

    public static System.Collections.Generic.List<string> GraphemeClusters(string s){

        System.Collections.Generic.List<string> ls = new System.Collections.Generic.List<string>();

        System.Globalization.TextElementEnumerator enumerator = System.Globalization.StringInfo.GetTextElementEnumerator(s);

        while(enumerator.MoveNext()){

            ls.Add((string)enumerator.Current);

        }

        return ls;

    }

    // Replace Grapheme Cluster

    public static string ReplaceGraphemeClusters(string s, string oldValue, string newValue){

        if(string.IsNullOrEmpty(s) || s.Length == 1){

            return s;

        }

        System.Collections.Generic.List<string> ls = GraphemeClusters(s);

        ls = ls.Select(r => r.Replace(oldValue, newValue)).ToList();

        return string.Join("", ls.ToArray());

    }

    public static void Main()

    {

        string s ="Mai Hung - Mai Hung Mise\u0301rables";

        string r = ReplaceGraphemeClusters(s, "é", "e");

        System.Console.WriteLine(s);

        System.Console.WriteLine(r);

    }

}