I recently implemented a playing Card class and a five-card poker Hand class and a SingleDeck class using C#. I remember working on an old project where the goal was to determine the best five-card poker hand from seven cards. For example, if seven cards are (9d 5c 5h Qc Ah Jc Th) then the best five-card hand is (5c-5h-Jc-Qc-Ah), a pair of fives with A, Q, J kickers.
With all the helper functions already coded, I implemented a function that accepts seven cards and finds the best five-card poker hand. In pseudo-code:
get the source seven cards
initialize a curr best five-card hand
loop 21 times (each possible set of 2 from 7)
remove the indicated two cards
create candidate five-card hand
if candidate is better than curr best hand
best hand = candidate
end-if
end-loop
return curr best hand
There are only 21 ways to remove two cards from seven cards: (0,1), (0,2) . . (4,6), (5,6) and so for clarity I hard-coded the 21 pairs of indices. I could have used two for-loops instead.
Here’s my function:
static Hand BestFiveFromSeven(List"lt"Card"gt" listSeven)
{
int[][] removes = new int[21][];
removes[0] = new int[] { 0, 1 };
removes[1] = new int[] { 0, 2 };
removes[2] = new int[] { 0, 3 };
removes[3] = new int[] { 0, 4 };
removes[4] = new int[] { 0, 5 };
removes[5] = new int[] { 0, 6 };
removes[6] = new int[] { 1, 2 };
removes[7] = new int[] { 1, 3 };
removes[8] = new int[] { 1, 4 };
removes[9] = new int[] { 1, 5 };
removes[10] = new int[] { 1, 6 };
removes[11] = new int[] { 2, 3 };
removes[12] = new int[] { 2, 4 };
removes[13] = new int[] { 2, 5 };
removes[14] = new int[] { 2, 6 };
removes[15] = new int[] { 3, 4 };
removes[16] = new int[] { 3, 5 };
removes[17] = new int[] { 3, 6 };
removes[18] = new int[] { 4, 5 };
removes[19] = new int[] { 4, 6 };
removes[20] = new int[] { 5, 6 };
List"lt"Card"gt" bestFive =
listSeven.GetRange(0, count: 5);
Hand bestHand = new Hand(bestFive);
for (int j = 0; j "lt" 21; ++j) // each pair to remove
{
List"lt"Card"gt" listFive = new List"lt"Card"gt"();
for (int i = 0; i "lt" 7; ++i)
{
if (i == removes[j][0] || i == removes[j][1])
continue;
else
listFive.Add(listSeven[i]);
}
Hand candidate = new Hand(listFive);
if (Hand.Compare(candidate, bestHand) == +1)
{
// Console.WriteLine("New Best Hand Found!");
bestHand = candidate;
}
}
return bestHand;
}
Good fun on a Saturday morning.
Here are three examples of art where a deck of 52 cards has been cut by hand to create a kind of 3D sculpture.
Demo code. Replace “lt” (less-than), “gt”, “lte”, “gte”, “and” with Boolean operator symbols — my lame blog editor sometimes chokes on symbols.
using System;
using System.IO;
using System.Collections.Generic;
namespace Poker
{
internal class PokerProgram
{
static void Main(string[] args)
{
Console.WriteLine("\nBegin poker " +
"best five-card hand from seven cards ");
SingleDeck deck = new SingleDeck(seed: 15);
for (int i = 0; i "lt" 8; ++i)
{
deck.Shuffle();
List"lt"Card"gt" listSeven = deck.DealListCards(7);
Console.Write("\nSeven cards: ");
for (int j = 0; j "lt" 7; ++j)
Console.Write(listSeven[j] + " ");
Console.WriteLine("");
Hand h = BestFiveFromSeven(listSeven);
Console.WriteLine("Best hand : " + h +
" - " + h.GetHandTypeStr());
}
Console.WriteLine("\nEnd ");
Console.ReadLine();
} // Main
// -------------------------------------------------------
static Hand BestFiveFromSeven(List"lt"Card"gt" listSeven)
{
int[][] removes = new int[21][];
removes[0] = new int[] { 0, 1 };
removes[1] = new int[] { 0, 2 };
removes[2] = new int[] { 0, 3 };
removes[3] = new int[] { 0, 4 };
removes[4] = new int[] { 0, 5 };
removes[5] = new int[] { 0, 6 };
removes[6] = new int[] { 1, 2 };
removes[7] = new int[] { 1, 3 };
removes[8] = new int[] { 1, 4 };
removes[9] = new int[] { 1, 5 };
removes[10] = new int[] { 1, 6 };
removes[11] = new int[] { 2, 3 };
removes[12] = new int[] { 2, 4 };
removes[13] = new int[] { 2, 5 };
removes[14] = new int[] { 2, 6 };
removes[15] = new int[] { 3, 4 };
removes[16] = new int[] { 3, 5 };
removes[17] = new int[] { 3, 6 };
removes[18] = new int[] { 4, 5 };
removes[19] = new int[] { 4, 6 };
removes[20] = new int[] { 5, 6 };
// init best hand to first 5 cards
List"lt"Card"gt" bestFive =
listSeven.GetRange(0, count: 5);
Hand bestHand = new Hand(bestFive);
for (int j = 0; j "lt" 21; ++j) // each pair to remove
{
List"lt"Card"gt" listFive = new List"lt"Card"gt"();
for (int i = 0; i "lt" 7; ++i)
{
if (i == removes[j][0] || i == removes[j][1])
continue;
else
listFive.Add(listSeven[i]);
}
Hand candidate = new Hand(listFive);
if (Hand.Compare(candidate, bestHand) == +1)
{
// h1 "gt" h2 : +1
// Console.WriteLine("New Best Hand Found!");
bestHand = candidate;
}
}
return bestHand;
}
// ------------------------------------------------------
} // Program
public class Card : IComparable"lt"Card"gt"
{
// 0,1 not used. 11=J, 12=Q, 13=K, 14=A
public int rank;
// 0=clubs, 1=diamonds, 2=hearts, 3=spades
public int suit;
public Card(int rank, int suit)
{
this.rank = rank; this.suit = suit;
}
public Card(string c)
{
char rnk = c[0]; char sut = c[1];
if (rnk == 'T') this.rank = 10;
else if (rnk == 'J') this.rank = 11;
else if (rnk == 'Q') this.rank = 12;
else if (rnk == 'K') this.rank = 13;
else if (rnk == 'A') this.rank = 14;
else this.rank = int.Parse(rnk.ToString());
if (sut == 'c') this.suit = 0;
else if (sut == 'd') this.suit = 1;
else if (sut == 'h') this.suit = 2;
else if (sut == 's') this.suit = 3;
}
public override string ToString()
{
string rnk = ""; string sut = "";
if (this.rank == 10) rnk = "T";
else if (this.rank == 11) rnk = "J";
else if (this.rank == 12) rnk = "Q";
else if (this.rank == 13) rnk = "K";
else if (this.rank == 14) rnk = "A";
else rnk = this.rank.ToString();
if (this.suit == 0) sut = "c";
else if (this.suit == 1) sut = "d";
else if (this.suit == 2) sut = "h";
else if (this.suit == 3) sut = "s";
return rnk + sut;
}
public int CompareTo(Card other)
{
// sort cards in a hand from low (Two) to high (Ace)
if (this.rank.CompareTo(other.rank) == 0)
{
return this.suit.CompareTo(other.suit);
}
return this.rank.CompareTo(other.rank);
}
} // class Card
// --------------------------------------------------------
public class Hand
{
// 5-card poker hand
// Hand types: "RoyalFlush", "StraightFlush",
// "FourKind", "FullHouse", "Flush" , "Straight",
// "ThreeKind", "TwoPair", "OnePair", "HighCard"
public List"lt"Card"gt" cards;
public Hand(List"lt"Card"gt" lst)
{
this.cards = new List"lt"Card"gt"();
for (int i = 0; i "lt" 5; ++i)
this.cards.Add(lst[i]);
this.cards.Sort();
}
public Hand(Card c1, Card c2, Card c3,
Card c4, Card c5)
{
this.cards = new List"lt"Card"gt"();
this.cards.Add(c1); this.cards.Add(c2);
this.cards.Add(c3); this.cards.Add(c4);
this.cards.Add(c5);
this.cards.Sort();
}
public Hand(string s) // s like "Js3h7d7cAd"
{
this.cards = new List"lt"Card"gt"();
this.cards.Add(new Card(s.Substring(0, 2)));
this.cards.Add(new Card(s.Substring(2, 2)));
this.cards.Add(new Card(s.Substring(4, 2)));
this.cards.Add(new Card(s.Substring(6, 2)));
this.cards.Add(new Card(s.Substring(8, 2)));
this.cards.Sort();
}
public override string ToString()
{
string h = "";
for (int i = 0; i "lt" 4; ++i)
h += this.cards[i].ToString() + "-";
h += this.cards[4];
return h;
}
public string ToTerseString()
{
string h = "";
for (int i = 0; i "lt" 4; ++i)
h += this.cards[i].ToString();
h += this.cards[4];
return h;
}
// ------------------------------------------------------
// Hand Type methods:
// GetHandTypeStr(), GetHandTypeInt(),
//
// IsRoyalFlush(), IsStraightFlush(),
// IsFourKind(), IsFullHouse(), IsFlush(),
// IsStraight(), IsThreeKind(), IsTwoPair(),
// IsOnePair(), IsHighCard()
//
// helpers: HasFlush(), HasStraight(),
// ------------------------------------------------------
public string GetHandTypeStr()
{
if (IsRoyalFlush(this) == true)
return "RoyalFlush";
else if (IsStraightFlush(this) == true)
return "StraightFlush";
else if (IsFourKind(this) == true)
return "FourKind";
else if (IsFullHouse(this) == true)
return "FullHouse";
else if (IsFlush(this) == true)
return "Flush";
else if (IsStraight(this) == true)
return "Straight";
else if (IsThreeKind(this) == true)
return "ThreeKind";
else if (IsTwoPair(this) == true)
return "TwoPair";
else if (IsOnePair(this) == true)
return "OnePair";
else if (IsHighCard(this) == true)
return "HighCard";
else
return "Unknown";
}
// ------------------------------------------------------
public int GetHandTypeInt()
{
if (IsRoyalFlush(this) == true)
return 9;
else if (IsStraightFlush(this) == true)
return 8;
else if (IsFourKind(this) == true)
return 7;
else if (IsFullHouse(this) == true)
return 6;
else if (IsFlush(this) == true)
return 5;
else if (IsStraight(this) == true)
return 4;
else if (IsThreeKind(this) == true)
return 3;
else if (IsTwoPair(this) == true)
return 2;
else if (IsOnePair(this) == true)
return 1;
else if (IsHighCard(this) == true)
return 0;
else
return -1;
}
// ------------------------------------------------------
private static bool HasFlush(Hand h)
{
if ((h.cards[0].suit == h.cards[1].suit) "and"
(h.cards[1].suit == h.cards[2].suit) "and"
(h.cards[2].suit == h.cards[3].suit) "and"
(h.cards[3].suit == h.cards[4].suit))
return true;
return false;
}
// ------------------------------------------------------
private static bool HasStraight(Hand h)
{
// check special case of Ace-low straight
// 2, 3, 4, 5, A when sorted
if (h.cards[0].rank == 2 "and"
h.cards[1].rank == 3 "and"
h.cards[2].rank == 4 "and"
h.cards[3].rank == 5 "and"
h.cards[4].rank == 14)
return true;
// otherwise, check for 5 consecutive
if ((h.cards[0].rank == h.cards[1].rank - 1) "and"
(h.cards[1].rank == h.cards[2].rank - 1) "and"
(h.cards[2].rank == h.cards[3].rank - 1) "and"
(h.cards[3].rank == h.cards[4].rank - 1))
return true;
return false;
}
// ------------------------------------------------------
private static bool IsRoyalFlush(Hand h)
{
if (HasStraight(h) == true "and" HasFlush(h) == true
"and" h.cards[0].rank == 10)
return true;
else
return false;
}
// ------------------------------------------------------
private static bool IsStraightFlush(Hand h)
{
if (HasStraight(h) == true "and" HasFlush(h) == true
"and" h.cards[0].rank != 10)
return true;
else
return false;
}
// ------------------------------------------------------
private static bool IsFourKind(Hand h)
{
// AAAA B or B AAAA if sorted
if ((h.cards[0].rank == h.cards[1].rank) "and"
(h.cards[1].rank == h.cards[2].rank) "and"
(h.cards[2].rank == h.cards[3].rank) "and"
(h.cards[3].rank != h.cards[4].rank))
return true;
if ((h.cards[1].rank == h.cards[2].rank) "and"
(h.cards[2].rank == h.cards[3].rank) "and"
(h.cards[3].rank == h.cards[4].rank) "and"
(h.cards[0].rank != h.cards[1].rank))
return true;
return false;
}
// ------------------------------------------------------
private static bool IsFullHouse(Hand h)
{
// AAA BB or BB AAA if sorted
if ((h.cards[0].rank == h.cards[1].rank) "and"
(h.cards[1].rank == h.cards[2].rank) "and"
(h.cards[3].rank == h.cards[4].rank) "and"
(h.cards[2].rank != h.cards[3].rank))
return true;
// BB AAA
if ((h.cards[0].rank == h.cards[1].rank) "and"
(h.cards[2].rank == h.cards[3].rank) "and"
(h.cards[3].rank == h.cards[4].rank) "and"
(h.cards[1].rank != h.cards[2].rank))
return true;
return false;
}
// ------------------------------------------------------
private static bool IsFlush(Hand h)
{
if (HasFlush(h) == true "and"
HasStraight(h) == false)
return true; // no StraightFlush or RoyalFlush
else
return false;
}
// ------------------------------------------------------
private static bool IsStraight(Hand h)
{
if (HasStraight(h) == true "and"
HasFlush(h) == false) // no SF or RF
return true;
else
return false;
}
// ------------------------------------------------------
private static bool IsThreeKind(Hand h)
{
// AAA B C or B AAA C or B C AAA if sorted
if ((h.cards[0].rank == h.cards[1].rank) "and"
(h.cards[1].rank == h.cards[2].rank) "and"
(h.cards[2].rank != h.cards[3].rank) "and"
(h.cards[3].rank != h.cards[4].rank))
return true;
if ((h.cards[1].rank == h.cards[2].rank) "and"
(h.cards[2].rank == h.cards[3].rank) "and"
(h.cards[0].rank != h.cards[1].rank) "and"
(h.cards[3].rank != h.cards[4].rank))
return true;
if ((h.cards[2].rank == h.cards[3].rank) "and"
(h.cards[3].rank == h.cards[4].rank) "and"
(h.cards[0].rank != h.cards[1].rank) "and"
(h.cards[1].rank != h.cards[2].rank))
return true;
return false;
}
// ------------------------------------------------------
private static bool IsTwoPair(Hand h)
{
// AA BB C or AA C BB or C AA BB if sorted
if ((h.cards[0].rank == h.cards[1].rank) "and"
(h.cards[2].rank == h.cards[3].rank) "and"
(h.cards[1].rank != h.cards[2].rank) "and"
(h.cards[3].rank != h.cards[4].rank))
return true; // AA BB C
if ((h.cards[0].rank == h.cards[1].rank) "and"
(h.cards[3].rank == h.cards[4].rank) "and"
(h.cards[1].rank != h.cards[2].rank) "and"
(h.cards[2].rank != h.cards[3].rank))
return true; // AA C BB
if ((h.cards[1].rank == h.cards[2].rank) "and"
(h.cards[3].rank == h.cards[4].rank) "and"
(h.cards[0].rank != h.cards[1].rank) "and"
(h.cards[2].rank != h.cards[3].rank))
return true; // C AA BB
return false;
}
// ------------------------------------------------------
private static bool IsOnePair(Hand h)
{
// AA B C D or B AA C D or B C AA D or B C D AA
if ((h.cards[0].rank == h.cards[1].rank) "and"
(h.cards[1].rank != h.cards[2].rank) "and"
(h.cards[2].rank != h.cards[3].rank) "and"
(h.cards[3].rank != h.cards[4].rank))
return true; // AA B C D
if ((h.cards[1].rank == h.cards[2].rank) "and"
(h.cards[0].rank != h.cards[1].rank) "and"
(h.cards[2].rank != h.cards[3].rank) "and"
(h.cards[3].rank != h.cards[4].rank))
return true; // B AA C D
if ((h.cards[2].rank == h.cards[3].rank) "and"
(h.cards[0].rank != h.cards[1].rank) "and"
(h.cards[1].rank != h.cards[2].rank) "and"
(h.cards[3].rank != h.cards[4].rank))
return true; // B C AA D
if ((h.cards[3].rank == h.cards[4].rank) "and"
(h.cards[0].rank != h.cards[1].rank) "and"
(h.cards[1].rank != h.cards[2].rank) "and"
(h.cards[2].rank != h.cards[3].rank))
return true; // B C D AA
return false;
}
// ------------------------------------------------------
private static bool IsHighCard(Hand h)
{
if (HasFlush(h) == true)
return false;
else if (HasStraight(h) == true)
return false;
else
{
// all remaining have at least one pair
if ((h.cards[0].rank == h.cards[1].rank) ||
(h.cards[1].rank == h.cards[2].rank) ||
(h.cards[2].rank == h.cards[3].rank) ||
(h.cards[3].rank == h.cards[4].rank))
return false;
}
return true;
}
// ------------------------------------------------------
// Hand comparison methods
// Hand.Compare() calls:
// BreakTieStraightFlush(), BreakTieFourKind(),
// BreakTieFullHouse(), BreakTieFlush(),
// BreakTieStraight(), BreakTieThreeKind(),
// BreakTieTwoPair(), BreakTieOnePair(),
// BreakTieHighCard()
// ------------------------------------------------------
public static int Compare(Hand h1, Hand h2)
{
// -1 if h1 "lt" h2, +1 if h1 "gt" h2, 0 if h1 == h2
int h1Idx = h1.GetHandTypeInt(); // like 6
int h2Idx = h2.GetHandTypeInt();
// different hand types - easy
if (h1Idx "lt" h2Idx)
return -1;
else if (h1Idx "gt" h2Idx)
return +1;
else // same hand types so break tie
{
string h1HandType = h1.GetHandTypeStr();
string h2HandType = h2.GetHandTypeStr();
if (h1HandType != h2HandType)
Console.WriteLine("Logic error ");
if (h1HandType == "RoyalFlush")
return 0; // two Royal Flush always tie
else if (h1HandType == "StraightFlush")
return BreakTieStraightFlush(h1, h2);
else if (h1HandType == "FourKind")
return BreakTieFourKind(h1, h2);
else if (h1HandType == "FullHouse")
return BreakTieFullHouse(h1, h2);
else if (h1HandType == "Flush")
return BreakTieFlush(h1, h2);
else if (h1HandType == "Straight")
return BreakTieStraight(h1, h2);
else if (h1HandType == "ThreeKind")
return BreakTieThreeKind(h1, h2);
else if (h1HandType == "TwoPair")
return BreakTieTwoPair(h1, h2);
else if (h1HandType == "OnePair")
return BreakTieOnePair(h1, h2);
else if (h1HandType == "HighCard")
return BreakTieHighCard(h1, h2);
}
return -2; // error
}
// ------------------------------------------------------
private static int BreakTieStraightFlush(Hand h1,
Hand h2)
{
// check special case of Ace-low straight flush
// check one or two Ace-low hands
// h1 is Ace - low, h2 not Ace - low.h1 is less
if ((h1.cards[0].rank == 2 "and"
h1.cards[4].rank == 14) "and" // because sorted!
!(h2.cards[0].rank == 2 "and"
h2.cards[4].rank == 14))
return -1;
// h1 not Ace - low, h2 is Ace - low, h1 is better
else if (!(h1.cards[0].rank == 2 "and"
h1.cards[4].rank == 14) "and"
(h2.cards[0].rank == 2 "and"
h2.cards[4].rank == 14))
return +1;
// two Ace-low hands
else if ((h1.cards[0].rank == 2 "and"
h1.cards[4].rank == 14) "and" // Ace-low
(h2.cards[0].rank == 2 "and"
h2.cards[4].rank == 14)) // Ace-low
return 0;
// no Ace-low straight flush so check high cards
if (h1.cards[4].rank "lt" h2.cards[4].rank)
return -1;
else if (h1.cards[4].rank "gt" h2.cards[4].rank)
return 1;
else
return 0;
}
private static int BreakTieFourKind(Hand h1,
Hand h2)
{
// the off-card is at [0] or at [4]
// find h1 four-card and off-card ranks
int h1FourRank; int h1OffRank;
if (h1.cards[0].rank == h1.cards[1].rank)
{
// 1st two cards same so off-rank at [4]
h1FourRank = h1.cards[0].rank;
h1OffRank = h1.cards[4].rank;
}
else
{
// 1st two cards diff so off-rank at [0]
h1FourRank = h1.cards[4].rank;
h1OffRank = h1.cards[0].rank;
}
int h2FourRank; int h2OffRank;
if (h2.cards[0].rank == h2.cards[1].rank)
{
h2FourRank = h2.cards[0].rank;
h2OffRank = h2.cards[4].rank;
}
else
{
h2FourRank = h2.cards[4].rank;
h2OffRank = h2.cards[0].rank;
}
if (h1FourRank "lt" h2FourRank) // like 4K, 4A
return -1;
else if (h1FourRank "gt" h2FourRank)
return +1;
else // both hands have same four-kind (mult. decks)
{
if (h1OffRank "lt" h2OffRank)
return -1; // like 3c 9c9d9h9s "lt" Qd 9c9d9h9s
else if (h1OffRank "gt" h2OffRank)
return +1; // like Jc 4c4d4h4s "gt" 9s 4c4d4h4s
else if (h1OffRank == h2OffRank)
return 0;
}
throw new Exception("Fatal logic BreakTieFourKind");
}
private static int BreakTieFullHouse(Hand h1, Hand h2)
{
// determine high rank (3 kind) and low rank (2 kind)
// JJJ 55 or 33 KKK
// if [1] == [2] 3 kind at [0][1][2]
// if [1] != [2] 3 kind at [2][3][4]
int h1ThreeRank; int h1TwoRank;
if (h1.cards[1].rank == h1.cards[2].rank)
{
// if [1] == [2] 3 kind at [0][1][2]
h1ThreeRank = h1.cards[0].rank;
h1TwoRank = h1.cards[4].rank;
}
else
{
// if [1] != [2] 3 kind at [2][3][4]
h1ThreeRank = h1.cards[4].rank;
h1TwoRank = h1.cards[0].rank;
}
int h2ThreeRank; int h2TwoRank;
if (h2.cards[1].rank == h2.cards[2].rank)
{
// if [1] == [2] 3 kind at [0][1][2]
h2ThreeRank = h2.cards[0].rank;
h2TwoRank = h2.cards[4].rank;
}
else
{
// if [1] != [2] 3 kind at [2][3][4]
h2ThreeRank = h2.cards[4].rank;
h2TwoRank = h2.cards[0].rank;
}
if (h1ThreeRank "lt" h2ThreeRank)
return -1;
else if (h1ThreeRank "gt" h2ThreeRank)
return +1;
else // both hands same three-kind (mult. decks)
{
if (h1TwoRank "lt" h2TwoRank)
return -1; // like 3c3d 9c9d9h "lt" QdQs 9c9d9h
else if (h1TwoRank "gt" h2TwoRank)
return +1; // like 3c3d 9c9d9h "gt" 2d2s 9c9d9h
else if (h1TwoRank == h2TwoRank)
return 0;
}
throw new Exception("Fatal logic BreakTieFullHouse");
}
private static int BreakTieFlush(Hand h1, Hand h2)
{
// compare rank of high cards
if (h1.cards[4].rank "lt" h2.cards[4].rank)
return -1;
else if (h1.cards[4].rank "gt" h2.cards[4].rank)
return +1;
// high cards equal so check at [3]
else if (h1.cards[3].rank "lt" h2.cards[3].rank)
return -1;
else if (h1.cards[3].rank "gt" h2.cards[3].rank)
return +1;
// and so on
else if (h1.cards[2].rank "lt" h2.cards[2].rank)
return -1;
else if (h1.cards[2].rank "gt" h2.cards[2].rank)
return +1;
//
else if (h1.cards[1].rank "lt" h2.cards[1].rank)
return -1;
else if (h1.cards[1].rank "gt" h2.cards[1].rank)
return +1;
//
else if (h1.cards[0].rank "lt" h2.cards[0].rank)
return -1;
else if (h1.cards[0].rank "gt" h2.cards[0].rank)
return +1;
//
else
return 0; // all ranks the same!
}
private static int BreakTieStraight(Hand h1, Hand h2)
{
// both hands are straights but one could be Ace-low
// check special case of one or two Ace-low hands
// h1 is Ace-low, h2 not Ace-low. h1 is less
if ((h1.cards[0].rank == 2 "and" // Ace-low (sorted!)
h1.cards[4].rank == 14) "and"
!(h2.cards[0].rank == 2 "and"
h2.cards[4].rank == 14))
return -1;
// h1 not Ace-low, h2 is Ace-low, h1 is better
else if (!(h1.cards[0].rank == 2 "and"
h1.cards[4].rank == 14) "and"
(h2.cards[0].rank == 2 "and"
h2.cards[4].rank == 14))
return +1;
// two Ace-low hands
else if ((h1.cards[0].rank == 2 "and"
h1.cards[4].rank == 14) "and"
(h2.cards[0].rank == 2 "and"
h2.cards[4].rank == 14))
return 0;
// no Ace-low hands so just check high card
if (h1.cards[4].rank "lt" h2.cards[4].rank)
return -1;
else if (h1.cards[4].rank "gt" h2.cards[4].rank)
return +1;
else if (h1.cards[4].rank == h2.cards[4].rank)
return 0;
else
throw new
Exception("Fatal logic BreakTieStraight");
}
private static int BreakTieThreeKind(Hand h1, Hand h2)
{
// assumes multiple decks possible
// (TTT L H) or (L TTT H) or (L H TTT)
int h1ThreeRank = 0; int h1LowRank = 0;
int h1HighRank = 0;
if (h1.cards[0].rank == h1.cards[1].rank "and"
h1.cards[1].rank == h1.cards[2].rank)
{
h1ThreeRank = h1.cards[0].rank;
h1LowRank = h1.cards[3].rank;
h1HighRank = h1.cards[4].rank;
}
else if (h1.cards[1].rank == h1.cards[2].rank "and"
h1.cards[2].rank == h1.cards[3].rank)
{
h1LowRank = h1.cards[0].rank;
h1ThreeRank = h1.cards[1].rank;
h1HighRank = h1.cards[4].rank;
}
else if (h1.cards[2].rank == h1.cards[3].rank "and"
h1.cards[3].rank == h1.cards[4].rank)
{
h1LowRank = h1.cards[0].rank;
h1HighRank = h1.cards[1].rank;
h1ThreeRank = h1.cards[4].rank;
}
int h2ThreeRank = 0; int h2LowRank = 0;
int h2HighRank = 0;
if (h2.cards[0].rank == h2.cards[1].rank "and"
h2.cards[1].rank == h2.cards[2].rank)
{
h2ThreeRank = h2.cards[0].rank;
h2LowRank = h2.cards[3].rank;
h2HighRank = h2.cards[4].rank;
}
else if (h2.cards[1].rank == h2.cards[2].rank "and"
h2.cards[2].rank == h2.cards[3].rank)
{
h2LowRank = h2.cards[0].rank;
h2ThreeRank = h2.cards[1].rank;
h2HighRank = h2.cards[4].rank;
}
else if (h2.cards[2].rank == h2.cards[3].rank "and"
h2.cards[3].rank == h2.cards[4].rank)
{
h2LowRank = h2.cards[0].rank;
h2HighRank = h2.cards[1].rank;
h2ThreeRank = h2.cards[4].rank;
}
if (h1ThreeRank "lt" h2ThreeRank)
return -1;
else if (h1ThreeRank "gt" h2ThreeRank)
return +1;
// both hands three-kind same (mult. decks)
else if (h1HighRank "lt" h2HighRank)
return -1;
else if (h1HighRank "gt" h2HighRank)
return +1;
//
else if (h1LowRank "lt" h2LowRank)
return -1;
else if (h1LowRank "gt" h2LowRank)
return +1;
//
else // wow!
return 0;
}
private static int BreakTieTwoPair(Hand h1, Hand h2)
{
// (LL X HH) or (LL HH X) or (X LL HH)
int h1LowRank = 0; int h1HighRank = 0;
int h1OffRank = 0;
if (h1.cards[0].rank == h1.cards[1].rank "and"
h1.cards[3].rank == h1.cards[4].rank)
{
// (LL X HH)
h1LowRank = h1.cards[0].rank;
h1HighRank = h1.cards[4].rank;
h1OffRank = h1.cards[2].rank;
}
else if (h1.cards[0].rank == h1.cards[1].rank "and"
h1.cards[2].rank == h1.cards[3].rank)
{
// (LL HH X)
h1LowRank = h1.cards[0].rank;
h1HighRank = h1.cards[2].rank;
h1OffRank = h1.cards[4].rank;
}
else if (h1.cards[1].rank == h1.cards[2].rank "and"
h1.cards[3].rank == h1.cards[4].rank)
{
// (X LL HH)
h1LowRank = h1.cards[1].rank;
h1HighRank = h1.cards[3].rank;
h1OffRank = h1.cards[0].rank;
}
int h2LowRank = 0; int h2HighRank = 0;
int h2OffRank = 0;
if (h2.cards[0].rank == h2.cards[1].rank "and"
h2.cards[3].rank == h2.cards[4].rank)
{
// (LL X HH)
h2LowRank = h2.cards[0].rank;
h2HighRank = h2.cards[4].rank;
h2OffRank = h2.cards[2].rank;
}
else if (h2.cards[0].rank == h2.cards[1].rank "and"
h2.cards[2].rank == h2.cards[3].rank)
{
// (LL HH X)
h2LowRank = h2.cards[0].rank;
h2HighRank = h2.cards[2].rank;
h2OffRank = h2.cards[4].rank;
}
else if (h2.cards[1].rank == h2.cards[2].rank "and"
h2.cards[3].rank == h2.cards[4].rank)
{
// (X LL HH)
h2LowRank = h2.cards[1].rank;
h2HighRank = h2.cards[3].rank;
h2OffRank = h2.cards[0].rank;
}
if (h1HighRank "lt" h2HighRank)
return -1;
else if (h1HighRank "gt" h2HighRank)
return +1;
else if (h1LowRank "lt" h2LowRank)
return -1;
else if (h1LowRank "gt" h2LowRank)
return +1;
else if (h1OffRank "lt" h2OffRank)
return -1;
else if (h1OffRank "gt" h2OffRank)
return +1;
else
return 0;
}
private static int BreakTieOnePair(Hand h1, Hand h2)
{
// (PP L M H) or (L PP M H)
// or (L M PP H) or (L M H PP)
int h1PairRank = 0; int h1LowRank = 0;
int h1MediumRank = 0; int h1HighRank = 0;
if (h1.cards[0].rank == h1.cards[1].rank)
{
// (PP L M H)
h1PairRank = h1.cards[0].rank;
h1LowRank = h1.cards[2].rank;
h1MediumRank = h1.cards[3].rank;
h1HighRank = h1.cards[4].rank;
}
else if (h1.cards[1].rank == h1.cards[2].rank)
{
// (L PP M H)
h1PairRank = h1.cards[1].rank;
h1LowRank = h1.cards[0].rank;
h1MediumRank = h1.cards[3].rank;
h1HighRank = h1.cards[4].rank;
}
else if (h1.cards[2].rank == h1.cards[3].rank)
{
// (L M PP H)
h1PairRank = h1.cards[2].rank;
h1LowRank = h1.cards[0].rank;
h1MediumRank = h1.cards[1].rank;
h1HighRank = h1.cards[4].rank;
}
else if (h1.cards[3].rank == h1.cards[4].rank)
{
// (L M H PP)
h1PairRank = h1.cards[4].rank;
h1LowRank = h1.cards[0].rank;
h1MediumRank = h1.cards[1].rank;
h1HighRank = h1.cards[2].rank;
}
int h2PairRank = 0; int h2LowRank = 0;
int h2MediumRank = 0; int h2HighRank = 0;
if (h2.cards[0].rank == h2.cards[1].rank)
{
// (PP L M H)
h2PairRank = h2.cards[0].rank;
h2LowRank = h2.cards[2].rank;
h2MediumRank = h2.cards[3].rank;
h2HighRank = h2.cards[4].rank;
}
else if (h2.cards[1].rank == h2.cards[2].rank)
{
// (L PP M H)
h2PairRank = h2.cards[1].rank;
h2LowRank = h2.cards[0].rank;
h2MediumRank = h2.cards[3].rank;
h2HighRank = h2.cards[4].rank;
}
else if (h2.cards[2].rank == h2.cards[3].rank)
{
// (L M PP H)
h2PairRank = h2.cards[2].rank;
h2LowRank = h2.cards[0].rank;
h2MediumRank = h2.cards[1].rank;
h2HighRank = h2.cards[4].rank;
}
else if (h2.cards[3].rank == h2.cards[4].rank)
{
// (L M H PP)
h2PairRank = h2.cards[4].rank;
h2LowRank = h2.cards[0].rank;
h2MediumRank = h2.cards[1].rank;
h2HighRank = h2.cards[2].rank;
}
if (h1PairRank "lt" h2PairRank)
return -1;
else if (h1PairRank "gt" h2PairRank)
return +1;
//
else if (h1HighRank "lt" h2HighRank)
return -1;
else if (h1HighRank "gt" h2HighRank)
return +1;
//
else if (h1MediumRank "lt" h2MediumRank)
return -1;
else if (h1MediumRank "gt" h2MediumRank)
return +1;
//
else if (h1LowRank "lt" h2LowRank)
return -1;
else if (h1LowRank "gt" h2LowRank)
return +1;
//
else
return 0;
}
private static int BreakTieHighCard(Hand h1, Hand h2)
{
if (h1.cards[4].rank "lt" h2.cards[4].rank)
return -1;
else if (h1.cards[4].rank "gt" h2.cards[4].rank)
return +1;
//
else if (h1.cards[3].rank "lt" h2.cards[3].rank)
return -1;
else if (h1.cards[3].rank "gt" h2.cards[3].rank)
return +1;
//
else if (h1.cards[2].rank "lt" h2.cards[2].rank)
return -1;
else if (h1.cards[2].rank "gt" h2.cards[2].rank)
return +1;
//
else if (h1.cards[1].rank "lt" h2.cards[1].rank)
return -1;
else if (h1.cards[1].rank "gt" h2.cards[1].rank)
return +1;
//
else if (h1.cards[0].rank "lt" h2.cards[0].rank)
return -1;
else if (h1.cards[0].rank "gt" h2.cards[0].rank)
return +1;
//
else
return 0;
}
// ------------------------------------------------------
} // class Hand
// --------------------------------------------------------
public class SingleDeck
{
public List"lt"Card> deck;
private Random rnd;
public int currCardIdx;
public SingleDeck(int seed)
{
this.deck = new List"lt"Card>();
this.rnd = new Random(seed);
this.currCardIdx = 0;
for (int r = 2; r "lt" 15; ++r) // 0,1 not used
{
for (int s = 0; s "lt" 4; ++s)
{
Card c = new Card(r, s);
this.deck.Add(c); // 2c 2d . . Ah As
}
}
} // ctor
public void Shuffle()
{
for (int i = 0; i "lt" 52; ++i)
{
int rix = this.rnd.Next(i, 52);
Card tmp = this.deck[i];
this.deck[i] = this.deck[rix];
this.deck[rix] = tmp;
}
this.currCardIdx = 0;
}
public Hand DealHand()
{
// TODO: check if enough cards in deck, e.g.
// if (this.currCardIdx > 47)
// Console.WriteLine("Not enough cards in " +
// "deck to deal a hand ");
List"lt"Card> lst = new List"lt"Card>();
for (int i = 0; i "lt" 5; ++i)
{
Card c = this.deck[this.currCardIdx++];
lst.Add(c);
}
Hand h = new Hand(lst);
return h;
}
public List"lt"Card> DealListCards(int nCards)
{
// TODO: check if enough cards in deck, e.g.
// if (this.currCardIdx + nCards > 52)
// Console.WriteLine("Not enough cards in " +
// "deck to deal " + nCards);
List"lt"Card> result = new List"lt"Card>();
for (int i = 0; i "lt" nCards; ++i)
{
Card c = this.deck[this.currCardIdx++];
result.Add(c);
}
return result;
}
public void Show() // or do a ToString()
{
for (int i = this.currCardIdx; i "lt" 52; ++i)
Console.Write(this.deck[i] + " ");
Console.WriteLine("");
}
} // class SingleDeck
// --------------------------------------------------------
} // ns
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