package CareerCupLibrary;
/* One node of a binary tree. The data element stored is a single
* character.
*/
public class TreeNode {
public int data;
public TreeNode left;
public TreeNode right;
public TreeNode parent;
public TreeNode(int d) {
data = d;
}
public void setLeftChild(TreeNode left) {
this.left = left;
if (left != null) {
left.parent = this;
}
}
public void setRightChild(TreeNode right) {
this.right = right;
if (right != null) {
right.parent = this;
}
}
public void insertInOrder(int d) {
if (d <= data) {
if (left == null) {
setLeftChild(new TreeNode(d));
} else {
left.insertInOrder(d);
}
} else {
if (right == null) {
setRightChild(new TreeNode(d));
} else {
right.insertInOrder(d);
}
}
}
public boolean isBST() {
if (left != null) {
if (data < left.data || !left.isBST()) {
return false;
}
}
if (right != null) {
if (data >= right.data || !right.isBST()) {
return false;
}
}
return true;
}
public int height() {
int leftHeight = left != null ? left.height() : 0;
int rightHeight = right != null ? right.height() : 0;
return 1 + Math.max(leftHeight, rightHeight);
}
public TreeNode find(int d) {
if (d == data) {
return this;
} else if (d <= data) {
return left != null ? left.find(d) : null;
} else if (d > data) {
return right != null ? right.find(d) : null;
}
return null;
}
private static TreeNode addToTree(int arr[], int start, int end){
if (end < start) {
return null;
}
int mid = (start + end) / 2;
TreeNode n = new TreeNode(arr[mid]);
n.setLeftChild(addToTree(arr, start, mid - 1));
n.setRightChild(addToTree(arr, mid + 1, end));
return n;
}
public static TreeNode createMinimalBST(int array[]) {
return addToTree(array, 0, array.length - 1);
}
}