public static void main(String[] args) {
		int[] array = {1,5,10,8,2,6,7,4,9,3};
		Node root = null;
		for(int i =0;i<10;i++){
			root = treeInsert(root,array[i]);
		}
		System.out.println("************ Inorder Tree walk ************");
		inorderTreeWalk(root);
		System.out.println();
		System.out.println("************ Inorder Tree walk ************");
		root = treeDelete(root,treeSearch(root,8));
		inorderTreeWalk(root);
		System.out.println();
		System.out.println("************ Preorder Tree walk ************");
		preorderTreeWalk(root);
		System.out.println();
		System.out.println("************ Postorder Tree walk ************");
		postorderTreeWalk(root);
		System.out.println();
		System.out.println();
		System.out.println(maximum(root).key);
		System.out.println(minimum(root).key);
		Node node  = treeSearch(root,-1);
		if(node != null)
			System.out.println(node.key);
		else
			System.out.println("no element.");
		
	}