public static void MultiplyAddToExt(ulong[] x, ulong[] y, ulong[] zz)
 {
     ulong[] array = Nat256.CreateExt64();
     SecT233Field.ImplMultiply(x, y, array);
     SecT233Field.AddExt(zz, array, zz);
 }
 public static void SquareAddToExt(ulong[] x, ulong[] zz)
 {
     ulong[] array = Nat256.CreateExt64();
     SecT233Field.ImplSquare(x, array);
     SecT233Field.AddExt(zz, array, zz);
 }