Problem 7a.

#fill
def random ():
 b= (334290+g.getTime(4))
 print int(b%100)
 return int(b%100)
 
def newrand ():
 x=random()
 while g.getPixel(x,0)==100:
  x=random()
 return x

def fill ():
 for a in range (0,25):
  x=newrand ()
  g.line (x,0,x,100)
  g.pause (1)
  
while 1:
 g.norefresh()
 g.paper (0)
 g.line (100,0,100,100)
 fill ()
 g.refresh ()
 for b in range (0,75):
  g.pause (5)


 fill ()
 g.refresh ()
 for b in range (0,50):
  g.pause (5)


 fill ()
 g.refresh ()

 for b in range (0,100):
   g.pause (5)

-gary escudero