[Derek Wyatt <tone_hole@yahoo.ca>, 2005-03-20 15.55 CET]
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Hash: SHA1This was a fun one
I'm looking forward to seeing other solutions.
Well, here is mine. I agree it was a fun one, except in the very long part
where I try to match different plays (what is the correct word?). Poker has
too many!
The strategy was nothing OO, or elegant. I just ordered the hand by rank (or
by suit when checking for flush) and tried to match some regexes. Probably
has bugs, the supplied card generator program never yielded a Royal Flush...
Here it is:
RANKS = "AKQJT98765432"
INTERNAL = "ABCDEFGHIJKLM"
RANKS_REVERSED = RANKS.reverse
ACE = "A"
LOW_ACE = "N"
# "plays"? maybe "figures"? (?)
PLAYS = {
"Royal Flush" => 10,
"Straight Flush" => 9,
"Four of a Kind" => 8,
"Full House" => 7,
"Flush" => 6,
"Straight" => 5,
"Three of a Kind" => 4,
"Double Pair" => 3,
"Pair" => 2,
"High Card" => 1,
"" => 0
}
class String
# split, do something with the array except finding, join, replace
# I never find the right method name...
def do! (method, low_ace=false, &block)
s = self.tr RANKS, INTERNAL
s.tr!(ACE, LOW_ACE) if low_ace
arr = s.split.send(method, &block)
s = arr.join(" ")
s.tr!(LOW_ACE, ACE) if low_ace
replace s.tr(INTERNAL, RANKS)
self
end
end
module Enumerable
# yields n items each time (but advances by one)
def each_n (n)
a =
each do |cur|
a << cur
next if a.size < n
yield *a
a.shift
end
end
end
# moves the used cards to the left, calculates hand score,
# creates hash to insert in hands array
# hand is the hand, name is name of the play (game?)
# m is the matched play (game? hand?)
# groups are the indices of the groups in m that form the hand
# I repeat, I'm very bad choosing method names
def finish (hand, name, m, *groups)
# extract the matched play (?) from hand,
# sort its parts from biggest to smallest (for the full house)
duphand = hand.dup
groups = groups.map {|g|
b = m.begin(g); e = m.end(g)
hand[b...e] = "*" * (e-b)
duphand.slice(b...e) }.
sort_by {|g| -g.size }
hand.delete!("*")
# if there are any remaining cards (kickers), sort them
if hand.size > 2
hand.do!(:sort)
end
# reinsert hand at the beginning
hand = groups.join(" ") + " " + hand
hand.squeeze!
# calculate score
# the score is a 5-digit hex number, each digit with
# the rank of the card at that position
# ups... can't use String#do! here 
score = hand.split[0,5].inject(1) { |sc, card|
(sc << 4) + RANKS_REVERSED.index(card[0].chr) }
# build the hash and return it
{ :hand => hand, :name => name, :score => score }
end
hands =
while line = gets
line.chomp!
if line.split.size != 7
hands << {:hand => line, :name => "", :score => 0}
next
end
line.do!(:sort)
catch :found do
# try to find...
# ... straight (and royal) flush
RANKS.split(//).each_n(5) do |a,b,c,d,e|
r = /(#{a}(.) #{b}\2 #{c}\2 #{d}\2 #{e}\2)/
if m = r.match(line)
hands << finish(line,
(m[0][0]==?A ? # if it starts with ace
"Royal Flush" : # it's royal
"Straight Flush"),
m, 1)
throw :found
end
end
# try to find straight flush with low ace
line.do!(:sort, true)
if m = /(5(.) 4\2 3\2 2\2 A\2)/.match(line)
hands << finish(line, "Straight Flush", m, 1)
throw :found
end
# ... four of a kind
line.do!(:sort)
if m = /((\w). \2. \2. \2.)/.match(line)
hands << finish(line, "Four of a Kind", m, 1)
throw :found
end
# ... full house
if m = /((\w)\w \2\w \2\w).*((\w)\w \4\w)/.match(line) or
m = /((\w)\w \2\w).*((\w)\w \4\w \4\w)/.match(line)
hands << finish(line, "Full House", m, 1, 3)
throw :found
end
# ...flush
# sort by color
line.do!(:sort_by){|card| [card[1],card[0]]}
if m = /(\w(\w) \w\2 \w\2 \w\2 \w\2)/.match(line)
hands << finish(line, "Flush", m, 1)
throw :found
end
# ...straight
line.do!(:sort)
RANKS.split(//).each_n(5) do |a,b,c,d,e|
r = /(#{a}. #{b}. #{c}. #{d}. #{e}.)/
if m = r.match(line)
hands << finish(line, "Straight", m, 1)
throw :found
end
end
# ...straight, low ace
line.do!(:sort, true)
if m = /(5. 4. 3. 2. A.)/.match(line)
hands << finish(line, "Straight", m, 1)
throw :found
end
# ... three of a kind
line.do!(:sort)
if m = /((\w)\w \2\w \2\w)/.match(line)
hands << finish(line, "Three of a Kind", m, 1)
throw :found
end
# ... double pair
if m = /((\w)\w \2\w).*((\w)\w \4\w)/.match(line)
hands << finish(line, "Double Pair", m, 1, 3)
throw :found
end
# ...pair
if m = /((\w)\w \2\w)/.match(line)
hands << finish(line, "Pair", m, 1)
throw :found
end
# ... high card.. FINISH AT LAST!!!
if m = /^(\w\w)/.match(line)
hands << finish(line, "High Card", m, 1)
throw :found
end
raise "This program is buggy. Terminating."
end
end
# get the winner hand
winner = hands.sort_by {|h| [-PLAYS[h[:name]], -h[:score]] }.first
# print the lines
hands.each do |h|
print h[:hand], " ", h[:name]
if winner[:name] != "" &&
h[:name] == winner[:name] &&
h[:score] == winner[:score]
print " (winner)"
end
puts
end
