Помогите исправить ошибку в коде.

 using Microsoft.VisualBasic; 





string input = Interaction.InputBox("Prompt", "Title", "Default", x_coordinate, y_coordinate); 

 using System; 

using System.Drawing; 

using System.Windows.Forms; 

 

 

namespace CircleDrawingApp

{ 

    public partial class Form1 : Form 

    { 

        private int n; 

        private Graphics g; 

        private Pen pen; 

        private System.Windows.Forms.Button button1; 

        private System.Windows.Forms.NumericUpDown numericUpDown1; 

 

        public Form1() 

        { 

            InitializeComponent(); 

            pen = new Pen(Brushes.Black, 2); 

            g = CreateGraphics(); 

 

            this.button1 = new System.Windows.Forms.Button(); 

            this.numericUpDown1 = new System.Windows.Forms.NumericUpDown(); 

            ((System.ComponentModel.ISupportInitialize)(this.numericUpDown1)).BeginInit(); 

 

            //  

            // button1 

            //  

            this.button1.Location = new System.Drawing.Point(100, 12); 

            this.button1.Name = "button1"; 

            this.button1.Size = new System.Drawing.Size(75, 23); 

            this.button1.TabIndex = 0; 

            this.button1.Text = "Draw"; 

            this.button1.UseVisualStyleBackColor = true; 

            this.button1.Click += new System.EventHandler(this.button1_Click); 

            //  

            // numericUpDown1 

            //  

            this.numericUpDown1.Location = new System.Drawing.Point(12, 12); 

            this.numericUpDown1.Name = "numericUpDown1"; 

            this.numericUpDown1.Size = new System.Drawing.Size(57, 20); 

            this.numericUpDown1.TabIndex = 0; 

            this.numericUpDown1.Value = new decimal(new int[] {5, 0, 0, 0}); 

 

            this.Controls.Add(this.button1); 

            this.Controls.Add(this.numericUpDown1); 

            ((System.ComponentModel.ISupportInitialize)(this.numericUpDown1)).EndInit(); 

 

        } 

 

        private void Form1_Load(object sender, EventArgs e) 

        { 

 

        } 

        private void DrawCircles(int n, int level, float x, float y, float radius) 

        { 

            if (level == n) 

                return; 

            g.DrawEllipse(pen, x - radius, y - radius, 2 * radius, 2 * radius); 

            System.Threading.Thread.Sleep(50); 

            pen.Color = Color.FromArgb(pen.Color.R, (pen.Color.G + 20) % 255, pen.Color.B); 

            DrawCircles(n, level + 1, x + 2 * radius, y, radius / 2); 

            pen.Color = Color.FromArgb(pen.Color.R, pen.Color.G, (pen.Color.B + 20) % 255); 

            DrawCircles(n, level + 1, x - 2 * radius, y, radius / 2); 

        } 

 

        private void button1_Click(object sender, EventArgs e) 

        { 

            button1.Enabled = false; 

            button1.Text = "Wait"; 

            Refresh(); 

            n = (int)numericUpDown1.Value; 

            DrawCircles(n, 0, Width / 2, Height / 2, Height / (n * 1.5f) ); 

            button1.Enabled = true; 

            button1.Text = "Draw"; 

        } 

    } 

}