using System;
using System.Windows.Forms;
using System.Drawing;

class form1: Form {
	private int maxLevel = 6;
	form1() {
		BackColor = Color.Black;
		this.Text = "シェルピンスキーのギャスケット";
		ClientSize = new Size(700, 500);
	}
	protected override void OnPaint(PaintEventArgs e) {
		DrawSierpinskiGasket(e.Graphics, 319, 40, 30, 430, 609, 430, 0);
		base.OnPaint(e);
	}
	private void DrawSierpinskiGasket(Graphics g, int x1, int y1, int x2, int y2, int x3, int y3, int level) {
		if (level == maxLevel)
		{
			g.DrawLine(Pens.Lime, x1, y1, x2, y2);
			g.DrawLine(Pens.Lime, x2, y2, x3, y3);
			g.DrawLine(Pens.Lime, x3, y3, x1, y1);
		}
		else
		{
			int xx1 = (int)((x1 + x2) / 2.0);
			int yy1 = (int)((y1 + y2) / 2.0);
			int xx2 = (int)((x2 + x3) / 2.0);
			int yy2 = (int)((y2 + y3) / 2.0);
			int xx3 = (int)((x3 + x1) / 2.0);
			int yy3 = (int)((y3 + y1) / 2.0);
			DrawSierpinskiGasket(g, x1, y1, xx1, yy1, xx3, yy3, level + 1);
			DrawSierpinskiGasket(g, x2, y2, xx1, yy1, xx2, yy2, level + 1);
			DrawSierpinskiGasket(g, x3, y3, xx3, yy3, xx2, yy2, level + 1);
		}
	}
	[STAThread]
	public static void Main() {
		Application.Run(new form1());
	}
}