public static MyTreeNode <int> S4_2_MinimalTree(int[] arr, int start, int end)
{
if (start > end)
{
return(null);
}
if (start == end)
{
return(new MyTreeNode <int>(arr[start]));
}
var midPoint = (start + end) / 2;
var root = new MyTreeNode <int>(midPoint);
root.LeftChild = S4_2_MinimalTree(arr, start, midPoint - 1);
root.RightChild = S4_2_MinimalTree(arr, midPoint + 1, end);
return(root);
}
public static MyTreeNode <int> S4_2_MinimalTree2(int[] arr)
{
if (arr.Length == 0)
{
return(null);
}
if (arr.Length == 1)
{
return(new MyTreeNode <int>(arr[0]));
}
var mid = arr.Length / 2;
var root = new MyTreeNode <int>(arr[mid]);
root.LeftChild = S4_2_MinimalTree2(arr.Take(mid).ToArray());
root.RightChild = S4_2_MinimalTree2(arr.Skip(mid).ToArray());
return(root);
}