public void It_should_return_false_if_BT_is_not_balanced()
{
var bt = new BinaryTreeNode(1);
bt.Left = new BinaryTreeNode(2);
bt.Left.Left = new BinaryTreeNode(3);
Obj.IsBalanced(bt).Should().BeFalse();
}
private int minDepth(BinaryTreeNode root)
{
if (root == null)
{
return 0;
}
return 1 + Math.Min(maxDepth(root.Left), maxDepth(root.Right));
}
public void BuildTrees()
{
T1= new BinaryTreeNode(6);
T1.Left = new BinaryTreeNode(271);
T1.Left.Left = new BinaryTreeNode(28);
T1.Left.Right = new BinaryTreeNode(0);
T1.Right = new BinaryTreeNode(561);
T1.Right.Right = new BinaryTreeNode(3);
T1.Right.Right.Left = new BinaryTreeNode(17);
}
private bool Check(BinaryTreeNode root, int min, int max)
{
if (root == null) {
return true;
} else if (root.Value < min || root.Value > max) {
return false;
}
return Check(root.Left, min, root.Value) && Check(root.Right, root.Value, max);
}
public bool Check(BinaryTreeNode T1, BinaryTreeNode T2)
{
if (T2 == null)
{
return true;
}
else
{
return IsSubTree(T1, T2);
}
}
public void InOrderTraverseRecursive(BinaryTreeNode root)
{
if (root == null) {
return;
}
InOrderTraverseRecursive(root.Left);
Result += root.Value.ToString();
Result += ",";
InOrderTraverseRecursive(root.Right);
}
public void It_should_return_true_if_root_is_a_BST()
{
var root = new BinaryTreeNode(7);
root.Left = new BinaryTreeNode(3);
root.Left.Left = new BinaryTreeNode(2);
root.Left.Right = new BinaryTreeNode(5);
root.Right = new BinaryTreeNode(11);
root.Right.Right = new BinaryTreeNode(17);
root.Right.Right.Left = new BinaryTreeNode(13);
Obj.Check(root).Should().BeTrue();
}
public void It_should_return_false_if_root_is_not_a_BST()
{
var root = new BinaryTreeNode(6);
root.Left = new BinaryTreeNode(271);
root.Left.Left = new BinaryTreeNode(28);
root.Left.Right = new BinaryTreeNode(0);
root.Right = new BinaryTreeNode(561);
root.Right.Right = new BinaryTreeNode(3);
root.Right.Right.Left = new BinaryTreeNode(17);
Obj.Check(root).Should().BeFalse();
}
private BinaryTreeNode BuildBSTFromSortedArrayHelper(int[] a, int start, int end)
{
if (start > end) {
return null;
}
var m = start + (end - start) / 2;
var node = new BinaryTreeNode(a[m]);
node.Left = BuildBSTFromSortedArrayHelper(a, start, m - 1);
node.Right = BuildBSTFromSortedArrayHelper(a, m + 1, end);
return node;
}
private bool IsSubTree(BinaryTreeNode R1, BinaryTreeNode R2)
{
if (R1 == null)
{
return false;
}
if (R1.Value == R2.Value)
{
if (IsMatchTree(R1, R2))
{
return true;
}
}
return (IsSubTree(R1.Left, R2) || IsSubTree(R1.Right, R2));
}
private bool IsMatchTree(BinaryTreeNode R1, BinaryTreeNode R2)
{
if (R2 == null && R1 == null)
{
return true; // nothing left in the subtree
}
if (R1 == null || R2 == null)
{
return false; // big tree empty & subtree still not found
}
if (R1.Value != R2.Value)
{
return false; // data doesn't match
}
return (IsMatchTree(R1.Left, R2.Left) &&
IsMatchTree(R1.Right, R2.Right));
}
public void LevelOrderTraverse(BinaryTreeNode root)
{
var q = new Queue<BinaryTreeNode>();
var curr = root;
q.Enqueue(curr);
while (q.Any()) {
var temp = q.Dequeue();
Result += temp.Value;
Result += ",";
if (temp.Left != null) {
q.Enqueue(temp.Left);
}
if (temp.Right != null) {
q.Enqueue(temp.Right);
}
}
}
public void InOrderTraverseIterative(BinaryTreeNode root)
{
var s = new Stack<BinaryTreeNode>();
var curr = root;
bool done = false;
while (!done) {
if (curr != null) {
// Go to the left-most leaf
s.Push(curr);
curr = curr.Left;
} else {
if (!s.Any()) {
done = true;
} else {
// Pop go to the right and do left subtree again
curr = s.Pop();
Result += curr.Value;
Result += ",";
curr = curr.Right;
}
}
}
}
/// <summary>
/// no two leaf nodes differ in distance from the root by more than one
/// </summary>
/// <returns><c>true</c> if the BT is balanced; otherwise, <c>false</c>.</returns>
/// <param name="root">Root</param>
public bool IsBalanced(BinaryTreeNode root)
{
return (maxDepth(root) - minDepth(root)) <= 1;
}
public bool Check(BinaryTreeNode root)
{
return Check(root, int.MinValue, int.MaxValue);
}
private BinaryTreeNode ReconstructBSTFromInOrderPreOrder(
int[] inorder, int[]preorder,
int inorderStart, int inorderEnd, int preIndex)
{
if (inorderStart > inorderEnd) {
return null;
}
var root = new BinaryTreeNode(preorder[preIndex++]);
if (inorderStart == inorderEnd) {
return root;
}
var rootIndex = Array.FindIndex(inorder, x => x == root.Value);
root.Left = ReconstructBSTFromInOrderPreOrder(
inorder, preorder,
inorderStart, rootIndex - 1, preIndex);
root.Right = ReconstructBSTFromInOrderPreOrder(
inorder, preorder,
rootIndex + 1, inorderEnd, preIndex);
return root;
}