static void Main(string [] args)
{
var st = new ST(10);
int [] a = { 3, 6, 1, 7, 2, 8, 4, 9, 10 };
st.Build(a);
st.Print();
st.Update(a, 3, 2);
st.Print();
Console.Write(st.Sum(a, 0, 10));
}
