import ch.aplu.turtle.*;
class serie5
{
Turtle pierre = new Turtle();
serie5()
  {
double a = 10;
while (a < 300)    
{
for (int i = 0; i < 4; i++)
      {
    pierre.forward(a); 
    a = a + 10 ;       
    pierre.right(90);  
      }   
}
}
public static void main(String[] args)
  {
    new serie5();
  }
}