public int?LowestCommonAncestor(DSBinarySearchNode <int> root, int v1, int v2)
{
if (root == null)
{
return(null);
}
if (v1 < root.Data && root.Data > v2)
{
return(LowestCommonAncestor(root.Left, v1, v2));
}
else if (v1 > root.Data && root.Data < v2)
{
return(LowestCommonAncestor(root.Right, v1, v2));
}
return(root.Data);
}
private static bool isValid(DSBinarySearchNode <int> root)
{
if (root == null)
{
return(true);
}
bool isLeftValid = true;
bool isRightValid = true;
if (root.Left != null)
{
if (root.Left.Data < root.Data)
{
isLeftValid = isValid(root.Left);
}
else
{
return(false);
}
}
if (root.Right != null)
{
if (root.Right.Data > root.Data)
{
isRightValid = isValid(root.Right);
}
else
{
return(false);
}
}
return(isLeftValid && isRightValid);
}
public static bool IsBinarySearchTree(DSBinarySearchNode <int> root)
{
/// Implement method to identify if the given tree is binary search tree or not. Return true if yes or else return false.
return(isValid(root));
}
public BinarySearchTreeIsValidTest()
{
this.Tree = new DSBinarySearchNode <int>(10);
}
