Java Program To Implement Fibonacci Heap

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import java.util.*;

class FibonacciHeapNode {
	FibonacciHeapNode child, left, right, parent;
	int element;

	public FibonacciHeapNode(int element) {
		this.right = this;
		this.left = this;
		this.element = element;
	}
}

class FibonacciHeap {
	private FibonacciHeapNode root;
	private int count;

	public FibonacciHeap() {
		root = null;
		count = 0;
	}

	public boolean isEmpty() {
		return root == null;
	}

	public void clear() {
		root = null;
		count = 0;
	}

	public void insert(int element) {
		FibonacciHeapNode node = new FibonacciHeapNode(element);
		node.element = element;

		if (root != null) {
			node.left = root;
			node.right = root.right;
			root.right = node;
			node.right.left = node;
			if (element < root.element)
				root = node;
		} else
			root = node;
		count++;
	}

	public void display() {
		System.out.print("\nHeap = ");
		FibonacciHeapNode ptr = root;
		if (ptr == null) {
			System.out.print("Empty\n");
			return;
		}
		do {
			System.out.print(ptr.element + " ");
			ptr = ptr.right;
		} while (ptr != root && ptr.right != null);
		System.out.println();
	}
}

public class JavaFibonacciHeapExample {

	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		System.out.println("FibonacciHeap Test\n\n");
		FibonacciHeap fh = new FibonacciHeap();

		char ch;

		do {
			System.out.println("\nFibonacciHeap Operations\n");
			System.out.println("1. insert element ");
			System.out.println("2. check empty");
			System.out.println("3. clear");

			int choice = scan.nextInt();
			switch (choice) {
			case 1:
				System.out.println("Enter element");
				fh.insert(scan.nextInt());
				break;
			case 2:
				System.out.println("Empty status = " + fh.isEmpty());
				break;
			case 3:
				fh.clear();
				break;
			default:
				System.out.println("Wrong Entry \n ");
				break;
			}
			fh.display();

			System.out.println("\nDo you want to continue (Type y or n) \n");
			ch = scan.next().charAt(0);
		} while (ch == 'Y' || ch == 'y');
	}
}

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