Pseudocode for progressing a poker game - algorithm

I'm creating a single function called progress() that is called after a player acts.
I think there are only 3 possible ways to end a poker game:
Game ends normally, there are 2 or more players until last round ends, do the "showdown" phase, and determine winners
Game ends abruptly, there is only one player remaining (all other players folded), that player wins, and his/her cards are not shown
Game ends fast-forward, there are no players who can act (e.g.: all players act "all-in"), the remaining community cards are drawn, do showdown and determine winners.
Here's the current pseudocode:
Determine 'players in game' (i.e. players who hasn't folded)
If there are two or more players in game
If there are players who hasn't acted
Start next player turn
Else (all players has acted)
If all players all-in, OR all players ALL-IN except one player
(If there are less than one player who can act)
Ends game fast-forward: showdown and determine winners
Else (two or more players who didn't act ALL-IN)
If this round is last round ('River')
Ends game normally: showdown and determine winners
Else
Begin next round
Else (there is only one player in game)
Ends game abruptly: that one remaining player wins
Is there anything I missed?

I think it's important to think in terms of betting rounds, not the
game as a whole. A poker hand is a sequence of betting rounds. At the
start of each round, some cards are dealt, some player is chosen to
act first, and then players are visited in order until the round ends.
Among the data you need to keep (it's a lot) is the identity of the
player who made the most recent raise in the current round (call him
"the agressor" even though it might just be big blind), and that
amount. The actions that end a betting round are these:
A player calls. Next player is the agressor.
End round, continue game.
A player folds. Next player is the agressor.
a. If more than one player has cards and unbet money, end round,
continue game as normal.
b. If two or more eligible players remain, but all but agressor
are all in, end round, continue game, but no more betting.
c. If only the agressor has cards, end game and round.
Do not deal any more cards.
If the game was not previously ended by (2c), then after the end
of the final betting round, showdown cards, award pots.
(Note: minor exception here for live blinds and straddles, so
add that bit in. And a bit of special-case code needed for the all-in for more than a call but less than a raise situation).
In pseudocode:
for each hand:
set "bluff" flag to false
clear all betting data
for each round:
if "bluff", break
deal some cards
while true:
visit each player
either force his action, or offer choices
if his action ends the round:
if it also ends the game (2c), set "bluff"
break (end round)
if "bluff", award all to bluffer.
else showdown, award pots as required

Related

Which algorithm combines knapsack optimization with the efficiency of job scheduling (to create a points optimizing fantasy basketball lineup)

I'm a fantasy basketball player and there is a recurring problem that I have not been able to figure out, and I can't find a similar enough example online that I can adapt for my own usage. For those who don't know, streaming (in fantasy basketball) is when you have an open spot on your individual team that you cycle available / free agent players through, in an attempt to maximize points, based on when they play during the week.
For example, Player 1 has games on Monday, Tuesday and Wednesday, and P2 plays on Thursday, Friday and Sunday. You keep P1 rostered through Wednesday, then drop them and pick up P2 for the rest of the week. Both players' points are added to your total; this allows you to essentially benefit from having two players' scoring for the week while only using one roster spot.
M
T
W
Th
F
S
S
Avg Pts / Game
P1
x
x
x
20
P2
x
x
x
25
The optimal strategy yields 135 points, vs 60 or 75 from just playing one player for the whole week.
The complexity comes from three places.
Players you want to play sometimes overlap on the same day, and their schedules often overlap in a way such that it might be worth it to start a worse player early in the week if it means you get access to a slate of their games later in the week. A player may have a lower points per game than another player, but by virtue of playing more games it’s worth it to start the player with a lower average.
Players can’t be re-added for the rest of the week once dropped, due to the nature of the fantasy sports platform. So you can’t toggle back and forth between two good players if they have complementary schedules. Related to this, there are a set number of “adds” you can use per week. Without this you could just add 7 different players, one each day, and figure out who was going to be the best for each day of the week. For the purposes of this league, the number of adds is 4 per week.
There are lots of available players. Figuring this out manually sometimes means starting players who are ranked far outside the top 130 (the total number of players across all of the leagues rosters) in Points Per Game, but due to their scheduling quirks, offer the best value for the remainder of the week. Trying each combination of players against each other involves a huge number of potential options.
I am a CS hobbyist, but the things I build do not require these sorts of optimizations, and I haven’t been able to find an example that would solve all parts of this problem.
Take the below schedule, for example. An “x” indicates the player is playing that day:
M
T
W
Th
F
S
S
Avg Pts / Game
P1
x
x
x
x
20
P2
x
x
x
21
P3
x
x
x
22
The points maximizing solution is to start Player 1 Monday, drop them and switch to Player 2 for the next three days, start no one on Thursday (as P1 would not be available after dropping them), and then switch to Player 3 for the last two days.
Start P1: 20 + 63 + 44 = 127
Constraints:
There are a set number of available days (7)
Only one player can be played per day
Each player can only be added one time (but can play consecutive games after being added with no penalty).
You can only add new players a set number of times: “n”
There are “p” possible players, each of whom has days of the week they can be played and an average points per game (same across all days)
The objective is to return the schedule of players in the proper combination that optimizes the total points in a given week.
My (somewhat brief) look through the existing algorithms led me to considering the knapsack problem, optimal scheduling, and greedy. Greedy doesn’t seem to work because it would immediately decide to start Player 3, which would not ultimately lead to the optimal solution, ending up with 125 total points
The scheduling algorithm would seem to require considering the start and end of a “task” as the first and last day a player plays, which creates problems here; Player 1’s “block” or whole week between first and last day would show that Player 1 offers the best total value at 80 points, and that the optimal strategy would be to just play them, but it doesn’t consider prematurely ending the task if something else was available.
Likewise I can’t figure out how to introduce the “switching” element into solutions to the knapsack problem.
There is a related question here but it doesn't include the scheduling aspect: Algorithm to select Player with max points but with a given cost
I feel like there’s a method that I’m not quite grasping, or a simplification that would allow me to use one of the aforementioned solutions. Any help in solving this completely inconsequential problem is greatly appreciated!

how to create schedule of championship?

My english is not very well, but i try to explain.
I must create a schedule for championship. We have 8 players. They play in one league. THeir will be 7 tournaments played in cup system. So, every player will be play with every player, and it's not problem:
schedule
I want to every player when he goes to semifinals play with every player two times (assuming they get promoted to semifinals). So player number one must play ones in quaterfinal with player 2, and two times when he get promoted to semifinals.

Complex pairing algorithm - team tournament

I would like to ask for help with an algorithm I’ve been working on for quite some time. I actually programmed it a few years ago using greedy pairing mostly but I’m not satisfied. Any help would be greatly appreciated!
So getting down to business. I have an application for tournament play (beachvolleyball to be precise, but should work for any pair-sport played in tournament format). The players show up on tournament day and gets randomly-ish put together with other participants and against other random teams. Top focus is to play as much as possible, however the number of players aren’t always divisible by the number of simultaneous playing spots. Therefor there will always be a number of players resting, standing the round out that is, and I’m trying to make sure this is as fair as possible by using 2 variables:
Rests (total number of rests during the day)
Rests in a row (Resting several games in a row, obviously)
The original concept of the tournament was mixing the teams with 1 male(m) and 1 female(f) in each team, playing against another team of m/f. However, the resting part is more important and there is often a lot more players of one sex than the other (i.e. 20 f and 7 m). Instead of letting the males play every single round, the program should make teams of f/f playing against f/f. Same-sex vs f/m should be avoided though.
Players should get new partners every round and play against new teams every round. Preferably you should play with all players of the opposite sex before playing with someone again. Players are allowed to come and leave as they like, and also take a break at any time (voluntary rest).
I’ve looked into the unstable marriage problem and the roommate problem, but my problem seems to be a mix of the two. Normally there will be two lists of players (m/f) and pairing, but under certain premises there should be teams made from just one list as described. Let me give you an example:
EXAMPLE:
43 players show up for a tournament with 6 courts.
17 Females (f) and 26 Males (m).
The 6 courts fit 12 teams with a total of 24 players per round.
Round 1
*12 m - 12 f*
*19 resting (5f, 14m)*
Round 2
5f and 14m have 1 rest and should play.
The best solution would be:
*4 f - 4 m*
*1f - 1m*
*4m - 4m*
*1f - 1m* (these players played last round as well).
In this example there will normally not be more than 1 rests in a row, if there woud’ve been 49 players from the start on the other hand..
In future updates, I’m also planning on letting the user choose number of players per team, and also to skip the m/f requisite.
Any thoughts?

Dots and boxes, even chains for 1st player, suggest move

I got to know that on a board of 3x3 box, player 1 should try to make even number of long chains. (long chain is a chain of length 3 or more). source
To summarize: (credit)
I need an even number of chains
I am player one, as an even number of moves has been made, and there are an even number of dots.
(This is known as the chain rule, and anyone who is unfamiliar with it should learn it as it is a key to winning dots and boxes. The number of squares already in chains means the winner of the chains battle in this game wins the majority of the squares by sacrificing two at the end of each of the chains they are given.)
I have been trying to play the game on this site but have been unable to win so far.
Attaching the board configuration when I got an even number of chains and its my turn to move.
What should be my move?
Can you give a winning strategy against the bot on this site?
What am I missing here? It seems to me that even though I got even number of long chains, no matter what move I make I will end up losing.
I didn't follow the YouTube link (readable text preferred) and don't know about the long chains. E.g., shouldn't we treat cycles differently from paths?
Still, in the given position, you can move anywhere on the right, giving the three right squares to your opponent and then taking the remaining six squares after his move.

Fair matchmaking for online games [closed]

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Most online games arbitrarily form teams. Often times its up to the user, and they'll choose a fast server with a free slot. This behavior produces unfair teams and people rage quit. By tracking a player's statics (or any statics that can be gathered) how can you choose teams that are as fair as possible?
One of the more well-known systems now is Microsoft's TrueSkill algorithm.
People have also attempted to adapt the Elo system for team matchmaking, though it's more designed for 1-v-1 pairings.
After my previous answer, I realized that if you wanted to get really fancy you could use a really simple but powerful idea: Markov Chains.
The intuitive idea behind using a Markov Chain goes something like this:
Create a graph G=(V,E)
Let each vertex in V represent an entity
Let each edge in E represent a transitioning probability between entities. This means that the sum of the out degrees of each vertex must be 1.
At the start (time t=0) assign each entity a unit value of 1
At each time step, transition form entity i, j by the transition probability defined in 3.
Let t->infinity then the value of each entity at t=infinity is the equilibrium (that is the chance of a transition into an entity is the same as the total chance of a transition out of an entity.)
This idea has for example been used successfully to implement Google's page rank algorithm. To describe how you can use it consider the following:
V = players E = probability of transitioning form player to player based on relative win/loss ratios
Each player is a vertex.
An edge from player A to B (B is not equal to A) has probability X/N where N is the total number of games played by A and X is the total games lost to B. Add an edge from A to A with probability M/N where M is the total number of games won by A.
Assign a skill level of 1 to each player at the start.
Use the Power Method to find the dominant eigenvector of the link matrix constructed from the probabilities defined in 3.
The dominant eigenvector is the amount of skill each player has at t=infinity, that is
the amount of skill each player has once the markov chain has come to equilibrium. This is a very robust measure of each players skill using the topology of the win/loss space.
Some caveats: there are several problems when applying this directly, the biggest problem will be seperated webs (that is your markov chain will not be irreducible and so the power method will not be guaranteed to converge.) Lucky for you, google has dealt with all these problems and more when implementing their page rank algorithm and all that remains for you is to look up how they circumvent these problems if you are so inclined.
One way would be to simply create a list of players looking for matches at any given time, sorted by player rank. Once you've reached enough people to start a new match (or perhaps, two less than the required), group them as such:
Remove best and worst player and put them on team 1
Remove now-best and now-worst player (really second-best and second worst) and put them on team 2
If there are only two players left, place each one on different teams, depending on who has the lowest combined score. Otherwise, repeat:
Remove now-best and now-worst and put them on team 1
Remove now-best and now-worst and put them on team 2
etc. etc. etc. until your teams are filled.
If you decided to start a new match with less than the required, then here it is time to let the players wait for new people to join. As soon as a new person joins, you're going to want to put them on the open team with the least combined score.
Alternatively, if you wanted to avoid games that combined good and bad players on the same team, you could split up everyone into tiers, (groups based on their ranking) and only match people within the same tier. This would require a new open/sorted list for each extra tier.
Example
Game is 4v4
A - 1000 pnts
B - 800 pnts
C - 600 pnts
D - 400 pnts
E - 200 pnts
F - 100 pnts
As soon as you get these six, group them into teams as such:
Team 1: A, F, D (combined score 1500)
Team 2: B, E, C (combined score 1600)
Now, we wait for two more players to join.
First, player E comes along with 500 pnts. He goes to Team 1, because they have a lower combined score.
Then, player F comes with 800 pnts. He goes to Team 2, because are the only open team left.
Total teams:
Team 1: A, F, D, E (combined score 2000)
Team 2: B, E, C, F (combined score 2400)
Note that the teams were actually pretty fair until the last two came in. To be honest, the best way would be to only create the match when you have enough players to start it. But then the wait times might be too long for the player.
Adjust with how much you need before forming the match. Lower = less wait time, more possibly unfair. Higher = more wait time, less possibly unfair.
If you have a pre-game screen, lower would also offer more time for people to chat and talk with their to-be teammates while waiting.
It is difficult to estimate the skill of any one player by a single metric and such a method is prone to abuse. However, if you only care about implementing something simple that will work well try the following:
keep track of wins and losses
use the percentage of wins vs losses as the statistic to match players ( in some sense of the word match, i.e. group players with similar percentages)
This has the obvious downfall of the case where a player may have a win-loss ratio of 5-0 and another of 50-20, the first has an infinite percentage while the other has a more reasonable percentage. It makes sense for the matching system to acknowledge this and be far more confident that the latter player has actual more skill because of the consistency required; however, pitting the two players against each other would probably be a good thing because the 5-0 player is probably trying to work the system by playing versus weaker players so pitting him against a consistently good player would do everyone good.
Note, I speak from experience from playing only strategy games such as Warcraft 3 where this is the typical match making behaviour. It seems to me like the percentage of wins over losses is a great metric by which to match players.
Match based on multiple attributes. I've implemented a simple matchmaking system using AWS Cloudsearch (based on Apache Solr). For example matching based on the a combination of following fields is possible
{
"fields": {
"elo_rating": 3121.44,
"points": 404,
"randomizer": 35,
"last_login": "2014-10-09T22:57:57Z",
"weapons": [
"CANNON",
"GUN"
]
}
It is now possible to run queries inclusive of multiple fields like the following.
(and (or weapons:'GUN' weapons:'CANNON' weapons:'DRONE')(and last_login:['2013-05-25T00:00:00Z','2014-10-25T00:00:00Z'])(and points:[100, 200])(and elo_rating:[1000, 2000]))}

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