import math

 import pygame, sys

 from pygame.locals import *

 pygame.init()

 screen = pygame.display.set_mode((600, 500))

 pygame.display.set_caption("The Pie Game -- Press 1 2 3 4")

 myfont = pygame.font.Font(None, 60)

 color = 200, 80, 60

 width = 5

 x = 300

 y = 250

 radius = 200

 position = x - radius, y - radius, radius*2,  radius*2 

 piece1 = False

 piece2 = False

 piece3 = False

 piece4 = False

 # main game loop

 while True:

     for event in pygame.event.get():

         if event.type == pygame.QUIT:

             pygame.quit()

             sys.exit()

         elif event.type == KEYUP:

             if event.key == pygame.K_ESCAPE:

                 pygame.quit()

                 sys.exit()

             elif event.key == pygame.K_1:

                 piece1 = True

             elif event.key == pygame.K_2:

                 piece2 = True

             elif event.key == pygame.K_3:

                 piece3 = True

             elif event.key == pygame.K_4:

                 piece4 = True

     #clear the screen

     screen.fill((0,0,200))

     textImg1 = myfont.render("", True, color)

     screen.blit(textImg1, (x+radius/2, y-radius/2))

     textImg2 = myfont.render("", True, color)

     screen.blit(textImg2, (x-radius/2, y-radius/2))

     textImg3 = myfont.render("", True, color)

     screen.blit(textImg3, (x-radius/2, y+radius/2))

     textImg4 = myfont.render("", True, color)

     screen.blit(textImg4, (x+radius/2, y+radius/2))

     #should the pieces be drawn?

     if piece1:

         start_angle = math.radians(0)

         end_angle   = math.radians(90)

         pygame.draw.arc(screen, color, position, start_angle, end_angle, width)

         pygame.draw.line(screen, color, (x, y), (x, y-radius), width)

         pygame.draw.line(screen, color, (x, y), (x+radius, y), width)

     if piece2:

         start_angle = math.radians(90)

         end_angle   = math.radians(180)

         pygame.draw.arc(screen, color, position, start_angle, end_angle, width)

         pygame.draw.line(screen, color, (x, y), (x, y-radius), width)

         pygame.draw.line(screen, color, (x, y), (x-radius, y), width)

     if piece3:

         start_angle = math.radians(180)

         end_angle   = math.radians(270)

         pygame.draw.arc(screen, color, position, start_angle, end_angle, width)

         pygame.draw.line(screen, color, (x, y), (x-radius, y), width)

         pygame.draw.line(screen, color, (x, y), (x, y+radius), width)

     if piece4:

         start_angle = math.radians(270)

         end_angle   = math.radians(360)

         pygame.draw.arc(screen, color, position, start_angle, end_angle, width)

         pygame.draw.line(screen, color, (x, y), (x, y+radius), width)

         pygame.draw.line(screen, color, (x, y), (x+radius, y), width)

     #finished?

     if piece1 and piece2 and piece3 and piece4:

         color = 0, 255, 0

     pygame.display.update()