static void Main(string[] args)
{
var ascii = new ASCIIEncoding();
var utf8 = new UTF8Encoding();
var a = ascii.GetUniqueSequence();
var b = ascii.GetNonUniqueSequence();
var c = ascii.IsUnique_UsingHash(a);
var d = ascii.IsUnique_UsingHash(b);
var nonAsciiChars = string.Concat(Enumerable.Repeat("𠀋𠍱𠌫𠈓1234abcd", 1000000));
}