VerticalOrderTraversal-1

class BinaryTree
{
    static int min = Integer.MAX_VALUE, max = Integer.MIN_VALUE;
    static void findVerticalOrder(Node root, HashMap<Integer, ArrayList<Integer>> hm, int hd)
    {
        if(root == null)
            return;
        ArrayList<Integer> al = hm.get(hd);
        if(al == null)
            al = new ArrayList<Integer>();
        al.add(root.data);
        hm.put(hd, al);
        if(hd < min)
            min = hd;
        if(hd > max)
            max = hd;
        
        findVerticalOrder(root.left, hm, hd-1);
        findVerticalOrder(root.right, hm, hd+1);
            
    }
    static void verticalOrder(Node root)
    {
        HashMap<Integer, ArrayList<Integer>> hm = new HashMap<Integer, ArrayList<Integer>>();
        int hd = 0;
        
        findVerticalOrder(root, hm, 0);
        
        for(int i=min ; i<=max ; i++)
        {
            ArrayList<Integer> al = hm.get(i);
            if(al == null)
                continue;
            for(int j=0 ; j<al.size() ; j++)
                System.out.print(al.get(j) + " ");
        }
    }
}