#include "library.h"

const int minx = 0, maxx = 800,
          sizey = 500;

double f(double x)
{ return 150 + 300*pow(sin(x/48), 2) + 25*cos(x/4); }

void plot(double x1, double x2)
{ if (x2-x1 < 0.5)
  { const double y1 = f(x1);
    const double y2 = f(x2);
    move_to(x1, y1);
    draw_to(x2, y2); }
  else
  { const double xm = (x1 + x2) / 2;
    plot(x1, xm);
    plot(xm, x2); } }
    

void main()
{ make_window(maxx, sizey);
  move_to(maxx/2, 0);
  draw_to(maxx/2, sizey);
  move_to(0, sizey/2);
  draw_to(maxx, sizey/2);
  move_to(maxx/2, sizey/2);
  write_string("0", direction::center);
  set_pen_width(3);
  plot(minx, maxx); }