lotto.py

# Lotto simulator ...
# here we let the user pick the winning numbers and the computer buys the tickets
#
# the user selects 6 unique random numbers from 1 to 50 and creates a list
# the computer generates similar lists and compares these lists with the user list
# whenever there are 3, 4, 5 or 6 matches, corresponding counters are updated
# finally all the matches are shown
# tested with Python24       vegaseat      14sep2006

import random
from collections import defaultdict, Counter

# The computer picks the numbers for each ticket sold
balls = 4
higher_ball = 100
tickets_sold = 10000000
cost_per_play = 0.1

def computer_random():
  return random.sample(range(1, higher_ball), balls)

def match_lists(list1, list2):

  # to find the number of matching items in each list use sets
  set1 = set(list1)
  set2 = set(list2)

  # set3 contains all items comon to set1 and set2
  set3 = set1.intersection(set2)

  # return number of matching items
  return len(set3)

# Picks the winning numbers
user_list = computer_random()

# Init Counter
matches_counts = defaultdict(int)

refund = 0
bigprize = 0
smallprize = 0
microprize = 0
fee = 0

print "\n# -- Lottery Statistics"
print "\nWinning numbers:", user_list
print "\nRandomizing %i Tickets from 1 to %i ..." % (tickets_sold, higher_ball)

for k in range(tickets_sold):

  # Random Generator
	comp_list = computer_random()
	matches = match_lists(comp_list, user_list)

	# Big Prize
	if matches == 1:
		refund += cost_per_play
	else:
		bigprize += cost_per_play * 0.20
		smallprize += cost_per_play * 0.30
		microprize += cost_per_play * 0.40

		# Fee
		fee += cost_per_play * 0.10

	# Increase Matches Counter
	matches_counts[matches] += 1

print "\nOut of %d tickets sold the computer found these matches:\n" % tickets_sold

for count in range(balls + 1):
	print " - Matching %i Numbers: %i" % (count, matches_counts[count])

print ''
print ' [1] - Refunded: %.08f BTCs' % refund

if matches_counts[2] == 0:
	print ' [2] - Micro Prize: %.08f BTCs : No winners :(' % microprize
else:
	print ' [2] - Micro Prize: %.08f BTCs : %.8f BTCs per winner' % (microprize, microprize / matches_counts[2])

if matches_counts[3] == 0:
	print ' [3] - Small Prize: %.08f BTCs : No winners :(' % (bigprize)
else:
	print ' [3] - Small Prize: %.08f BTCs : %.8f BTCs per winner' % (smallprize, smallprize / matches_counts[3])

if matches_counts[4] == 0:
	print ' [4] - Big Prize: %.08f BTCs : No winners :(' % (bigprize)
else:
	print ' [4] - Big Prize: %.08f BTCs : %.8f BTCs per winner' % (bigprize, bigprize / matches_counts[4])

print "\n House Fees: %.08f" % fee
print ''