private static bool IsBst(Tree a, int small, int large)
{
if (a == null)
return true;
if (a.value > small && a.value < large)
{
bool IsLeftBST = IsBst(a.left, small, a.value);
bool IsRightBST = IsBst(a.right, a.value, large);
return IsLeftBST && IsRightBST;
}
return false;
}
static void Main(string[] args)
{
// Build Tree
// 4
// 2 6
// 1 3 5 7
Tree myTree = new Tree(4);
myTree.left = new Tree( 2);
myTree.right = new Tree(6);
myTree.left.left = new Tree(1);
myTree.left.right = new Tree(3);
myTree.right.left = new Tree(5);
myTree.right.right = new Tree(7);
Console.WriteLine("Is My Tree BST ? " + IsBst(myTree, Int32.MinValue, Int32.MaxValue));
Console.ReadKey();
}
public Tree(int val)
{
value = val;
left = right = null;
}