Class Add in C# Error Ocure

using System;
using System.Collections.Generic;
using System.Linq;
using System.Drawing;
using System.Text;

namespace WindowsFormsApplication3
{
    public class Class1
    {
        public Rectangle[] Snakerec;
        public SolidBrush Brush;

        private int x, y, height, width;

        public void Snake()
        {
            Snakerec = new Rectangle[3];
            Brush = new SolidBrush(Color.Blue);

            x = 20;
            y = 0;
            height = 10;
            width = 10;

            for (int i = 0; i < Snakerec.Length; i++)
            {
                Snakerec[i] = new Rectangle(x, y, width, height);
                x -= 10;
            }
        }
        public void Drawsnake(Graphics paper)
        {
            try
            {
                foreach(Rectangle rec in Snakerec)
                {
                    paper.FillRectangle(Brush, rec);
                }
            }
            catch (Exception ex)
            {
                string st = ex.Message;

            }
        }
    }
}