BTLEFTVIEW

node and key value*/
class Node {
	int data;
	Node left, right;

	public Node(int item)
	{
		data = item;
		left = right = null;
	}
}

/* Class to print the left view */
class BinaryTree {
	Node root;
	static int max_level = 0;

	// recursive function to print left view
	void leftViewUtil(Node node, int level)
	{
		// Base Case
		if (node == null)
			return;

		// If this is the first node of its level
		if (max_level < level) {
			System.out.print(node.data + " ");
			max_level = level;
		}

		// Recur for left and right subtrees
		leftViewUtil(node.left, level + 1);
		leftViewUtil(node.right, level + 1);
	}

	// A wrapper over leftViewUtil()
	void leftView()
	{
		max_level = 0;
		leftViewUtil(root, 1);
	}

	/* testing for example nodes */
	public static void main(String args[])
	{
		/* creating a binary tree and entering the nodes */
		BinaryTree tree = new BinaryTree();
		tree.root = new Node(10);
		tree.root.left = new Node(2);
		tree.root.right = new Node(3);
		tree.root.left.left = new Node(7);
		tree.root.left.right = new Node(8);
		tree.root.right.right = new Node(15);
		tree.root.right.left = new Node(12);
		tree.root.right.right.left = new Node(14);

		tree.leftView();
	}
}