#codingexercise
Int MaxR (ref List <int>  items, int start, int end)
{
If (start > end || items == null || items.length == 0 || start < 0 || end >= items.length) throw new Exception();
If (start == end) return items [start];
Int mid = checked ( (start + end) / 2);
Int left = MaxR (ref items, start, mid);
Int right = MaxR (ref items, mid +1, end);
Return left > right ? Left : right;
}