/************************************************
Grundlegende Algorithmen mit Java,
http://algorithmen-und-problemloesungen.de/
Copyright @2007-2008 by Doina Logofatu

in C#: Michael Gärtner
************************************************/

using System;
using System.IO;

namespace Logofatu
{
    class P9QuadratRek
    {
        private static String FileInputName = "quadrate.in";
        private static String FileOutputName = "quadrate.out";

        private int step = 0;
               
        private bool inSquare(int x0, int y0, int cx, int cy, int k)
        {
            int x1 = cx - k;
            int x2 = cx + k;
            int y1 = cy - k;
            int y2 = cy + k;
            return (x1 <= x0 && x0 <= x2 && y1 <= y0 && y0 <= y2);
        }

        public void count(int x0, int y0, int cx, int cy, int k)
        {
            int x1, x2, y1, y2;
            if ( inSquare(x0,y0,cx,cy,k) )
              step++;
            if ( k > 1 )
            {
                x1 = cx - k;
                x2 = cx + k;
                y1 = cy - k;
                y2 = cy + k;
                count(x0, y0, x1, y1, k / 2);
                count(x0, y0, x1, y2, k / 2);
                count(x0, y0, x2, y1, k / 2);
                count(x0, y0, x2, y2, k / 2);
            }            
        }

        static void Main(string[] args)
        {
            StreamReader sr = null;
            StreamWriter sw = null;
            try
            {
                int k, x0, y0;
                sr = new StreamReader(FileInputName);
                sw = new StreamWriter(FileOutputName);

                while ( !sr.EndOfStream )
                {
                    string[] sArray = sr.ReadLine().Split(' ');
                    k = int.Parse(sArray[0]);
                    x0 = int.Parse(sArray[1]);
                    y0 = int.Parse(sArray[2]);
                    P9QuadratRek q = new P9QuadratRek();
                    q.count(x0, y0, 1024, 1024, k);
                    sw.WriteLine(q.step);
                }
            }
            catch ( IOException ex )
            {
                Console.WriteLine("Fehler bei der Dateiverarbeitung!\n" + ex);
            }
            finally
            {
                if ( sr != null )
                {
                    sr.Close();
                }
                if ( sw != null )
                {
                    sw.Close();
                }
            }
        }
    }
}