make a famous painting:
   prepare the canvas;
   stain it diligently;
   painting is finished.


prepare the canvas:
   enter graphics mode;
   INT CONST xmin :: graphics x limit DIV 10,
             ymin :: graphics y limit DIV 10,
             xmax :: graphics x limit - xmin,
             ymax :: graphics y limit - ymin;
   INT VAR k, l, x, y;
   move (xmin, ymin);
   draw (xmin, ymax);
   draw (xmax, ymax);
   draw (xmax, ymin);
   draw (xmin, ymin).


stain it diligently:
   FOR k FROM 1 UPTO 150
   REP
     x := random (2 * xmin, xmax - xmin);
     y := random (2 * ymin, ymax - ymin);
     l := int (real (ymin) * (1.0 - sqrt (random)));
     IF random > 0.5
     THEN
       move (x - l, y);
       draw (x + l, y)
     ELSE
       move (x, y - l);
       draw (x, y + l)
     FI
   ENDREP.


painting is finished:
   wait for confirmation (5, 5);
   leave graphics mode.