initial commit

Author: aashishmalik

BinarySearchTree/BST.java

@@ -0,0 +1,258 @@
+package BinarySearchTree;
+
+public class BST {
+
+	private class Node {
+		int data;
+		Node left;
+		Node right;
+	}
+
+	private Node root;
+
+	public BST(int[] in) {
+
+		this.root = construct(in, 0, in.length - 1);
+
+	}
+
+	private Node construct(int[] in, int ilo, int ihi) {
+
+		if (ilo > ihi)
+			return null;
+
+		int mid = (ilo + ihi) / 2;
+
+		Node nn = new Node();
+		nn.data = in[mid];
+
+		nn.left = construct(in, ilo, mid - 1);
+		nn.right = construct(in, mid + 1, ihi);
+
+		return nn;
+	}
+
+	public void display() {
+
+		display(this.root);
+	}
+
+	private void display(Node node) {
+
+		if (node == null) {
+			return;
+		}
+
+		String str = "";
+
+		if (node.left != null)
+			str += node.left.data;
+
+		str += " ->" + node.data + "<- ";
+
+		if (node.right != null)
+			str += node.right.data;
+
+		System.out.println(str);
+
+		display(node.left);
+
+		display(node.right);
+
+	}
+
+	public int size() {
+		return size(this.root);
+	}
+
+	private int size(Node node) {
+
+		if (node == null)
+			return 0;
+
+		int lsum = size(node.left);
+		int rsum = size(node.right);
+
+		return lsum + rsum + 1;
+	}
+
+	public int max() {
+		return max(this.root);
+	}
+
+	private int max(Node node) {
+
+		if (node == null)
+			return Integer.MIN_VALUE;
+
+		if (node.right != null)
+			return max(node.right);
+		else
+			return node.data;
+	}
+
+	public int height() {
+		return height(this.root);
+	}
+
+	private int height(Node node) {
+
+		if (node == null)
+			return -1;
+		int lh, rh;
+
+		lh = height(node.left);
+
+		rh = height(node.right);
+
+		return Math.max(lh, rh) + 1;
+	}
+
+	public boolean find(int item) {
+		return find(this.root, item);
+	}
+
+	private boolean find(Node node, int item) {
+
+		if (node == null) {
+			return false;
+		}
+		if (item < node.data)
+			return find(node.left, item);
+		else if (item > node.data)
+			return find(node.right, item);
+		else
+			return true;
+
+	}
+
+	public void printDesc() {
+		printDesc(this.root);
+	}
+
+	private void printDesc(Node node) {
+
+		if (node == null)
+			return;
+		printDesc(node.right);
+
+		System.out.print(node.data + " ");
+		printDesc(node.left);
+
+	}
+
+	public void printLowHi(int lo, int hi) {
+		printLowHi(this.root, lo, hi);
+	}
+
+	private void printLowHi(Node node, int lo, int hi) {
+
+		if (node == null)
+			return;
+
+		if (node.data >= hi)
+			printLowHi(node.left, lo, hi);
+		else if (node.data < lo)
+			printLowHi(node.right, lo, hi);
+		else {
+			printLowHi(node.left, lo, hi);
+			System.out.print(node.data + " ");
+			printLowHi(node.right, lo, hi);
+		}
+	}
+
+	class HeapMover {
+		int sum;
+	}
+
+	public void replaceLarger() {
+
+		replaceLarger(this.root, new HeapMover());
+	}
+
+	private void replaceLarger(Node node, HeapMover mover) {
+
+		if (node == null)
+			return;
+
+		replaceLarger(node.right, mover);
+		int temp = node.data;
+		node.data = mover.sum;
+		mover.sum += temp;
+		replaceLarger(node.left, mover);
+
+	}
+
+	public void addItem(int item) {
+		addItem(this.root, item);
+	}
+
+	private void addItem(Node node, int item) {
+
+		if (node.data > item) {
+			if (node.left != null)
+				addItem(node.left, item);
+			else {
+				Node nn = new Node();
+				nn.data = item;
+				node.left = nn;
+			}
+		} else {
+			if (node.right != null)
+				addItem(node.right, item);
+			else {
+				Node nn = new Node();
+				nn.data = item;
+				node.right = nn;
+			}
+		}
+	}
+
+	public void remove(int item) {
+
+		remove(this.root, null, item);
+
+	}
+
+	private void remove(Node node, Node parent, int item) {
+		if (node == null) {
+			return;
+		}
+		if (node.data < item) {
+			remove(node.right, node, item);
+		} else if (node.data > item) {
+			remove(node.left, node, item);
+		} else {
+			if (node.left == null && node.right == null) {
+
+				if (parent.left == node)
+					parent.left = null;
+				else
+					parent.right = null;
+
+			} else if (node.left != null && node.right == null) {
+
+				if (parent.left == node)
+					parent.left = node.left;
+				else
+					parent.right = node.left;
+
+			} else if (node.right != null && node.left == null) {
+
+				if (parent.right == node)
+					parent.right = node.right;
+				else
+					parent.left = node.right;
+
+			} else {
+
+				int temp = max(node.left);
+				remove(node.left, node, temp);
+				node.data = temp;
+
+			}
+		}
+
+	}
+
+}

BinarySearchTree/Client.java

@@ -0,0 +1,30 @@
+package BinarySearchTree;
+
+public class Client {
+
+	public static void main(String[] args) {
+
+		int[] in = { 10, 20, 30, 40, 50, 60, 70, 80, 90 };
+		BST bst = new BST(in);
+		bst.display();
+//		System.out.println();
+//		// bst.printDesc();
+//		// System.out.println(bst.find(50));
+//		// System.out.println(bst.max());
+//		System.out.println();
+//		System.out.println("==============");
+//		// bst.printLowHi(15, 85);
+//		// bst.replaceLarger();
+//		System.out.println();
+//		System.out.println("==================");
+//		bst.display();
+		System.out.println("================");
+//		bst.addItem(55);
+//		bst.display();
+//		System.out.println(bst.max());
+		bst.remove(50);
+		bst.display();
+
+	}
+
+}