public override string ToString()
{
string result = "";
int height = GetHeight (this);
Console.WriteLine ("height = " + height);
BTNode dummy = new BTNode (-1);
List<BTNode> curLevel = new List<BTNode>();
curLevel.Add (this);
for (int i = 0; i < height; ++i) {
string indent = new string ('\t', (int)Math.Pow (2, height - i - 1));
string sep = new string ('\t', (int)Math.Pow (2, height - i));
result += indent;
List<BTNode> nextLevel = new List<BTNode> ();
foreach (BTNode n in curLevel) {
if (n == dummy)
result += sep;
else
result += n.data.ToString() + sep;
nextLevel.Add (n.left ?? dummy);
nextLevel.Add (n.right ?? dummy);
}
result += '\n';
curLevel = nextLevel;
}
return result;
}
public static BTNode CreateMinimalBST(int[] arr, int left, int right)
{
if (left > right)
return null;
int mid = left + (right - left) / 2;
BTNode n = new BTNode (arr [mid]);
n.left = CreateMinimalBST (arr, left, mid - 1);
n.right = CreateMinimalBST (arr, mid + 1, right);
return n;
}
private int GetHeight(BTNode node)
{
if (node == null)
return 0;
int leftHeight = GetHeight (node.left);
int rightHeight = GetHeight (node.right);
return 1 + Math.Max (leftHeight, rightHeight);
}
public BTNode(int data)
{
this.data = data;
this.parent = null;
}
public BTNode(int data)
{
this.data = data;
this.parent = null;
}
