public static List <UBSTNode> generateTrees(int n)
{
List <UBSTNode> ls = new List <UBSTNode>();
ls.Add(null);
_dict[0] = ls;
ls = new List <UBSTNode>();
ls.Add(new UBSTNode(1, null, null));
_dict[1] = ls;
for (int i = 2; i <= n; i++)
{
ls = new List <UBSTNode>();
for (int j = 1; j <= i; j++)
{
foreach (UBSTNode left in _dict[j - 1])
{
foreach (UBSTNode right in _dict[i - j])
{
UBSTNode nRoot = new UBSTNode(j, null, null);
nRoot.left = left;
nRoot.right = DeepCopyIncrease(right, j);
ls.Add(nRoot);
}
}
}
_dict[i] = ls;
}
return(_dict[n]);
}
public static UBSTNode DeepCopyIncrease(UBSTNode n, int d)
{
if (n == null)
{
return(null);
}
UBSTNode newRoot = new UBSTNode(n._d + d, null, null);
newRoot.left = DeepCopyIncrease(n.left, d);
newRoot.right = DeepCopyIncrease(n.right, d);
return(newRoot);
}
public UBSTNode(int d, UBSTNode l, UBSTNode r)
{
_d = d;
left = l;
right = r;
}
