cards/HandCompareUtils.java at master · scooter3/cards · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
package com.pslin.cards;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author plin
 */
public class HandCompareUtils {

    public static void main(String[] args) {
//        Hand straight = CardGenerator.getStraight(3, 7);
//        System.out.println(straight.toString());
//        System.out.println(isStraight(straight));
//
//        Hand flush = CardGenerator.getFlush(Card.Suit.SPADE);
//        System.out.println(flush.toString());
//        System.out.println(isFlush(flush));
//
//        Hand random = CardGenerator.getFiveRandom();
//        System.out.println(random.toString());
//        System.out.println(isFlush(random));

        Hand fullHouse = CardGenerator.getFullHouse(14, 3);
        System.out.println(fullHouse.toString());
        System.out.println(isFullHouse(fullHouse));


    }

//    public boolean compareHands(Hand hand1, Hand hand2) {
//        if(hand1.getCards().size() != hand2.getCards().size()) {
//            throw new RuntimeException("Cannot compare hands: different sizes.");
//        }
//
//
//    }

    /**
     * Determines if a hand is a straight.
     *
     * @param hand
     * @return true if hand is a straight
     */
    public static boolean isStraight(Hand hand) {
        List<Card> cards = hand.getCards();

        if(cards.size() < 5) {
            return false;
        }

        Collections.sort(cards);
        Card previousCard = null;

        for(Card card : cards) {
            if(previousCard == null) {
                previousCard = card;
                continue;
            }
            // check difference between current and previous is not 1, it is not a straight
            if(card.getValue() - previousCard.getValue() != 1) {
                return false;
            }

            previousCard = card;
        }

        return true;
    }

    /**
     * Determines if a hand is a flush.
     *
     * @param hand
     * @return true if hand is a flush
     */
    public static boolean isFlush(Hand hand) {
        List<Card> cards = hand.getCards();

        if(cards.size() < 5) {
            return false;
        }

        Card.Suit suit = null;

        for(Card card : cards) {
            if(suit == null) {
                suit = card.getSuit();
                continue;
            }
            if(suit != card.getSuit()) {
                return false;
            }
        }

        return true;
    }

    public static boolean isFullHouse(Hand hand) {
        Map<Integer, List<Card>> cardMap = new HashMap<>();
        List<Card> cards = hand.getCards();

        if(cards.size() < 5) {
            return false;
        }

        for(Card card : cards) {
            List<Card> list = cardMap.get(card.getValue());

            // if list is null, then create a new one and add it to the map
            if(list == null) {
                list = new ArrayList<>();
                cardMap.put(card.getValue(), list);
            }

            list.add(card);
        }

        // if there are more than 2 distinct card values, it is not a full house
        if(cardMap.size() != 2) {
            return false;
        }

        int previousSet = 0;
        for(Map.Entry<Integer, List<Card>> entry : cardMap.entrySet()) {
            if(previousSet == 0) {
                previousSet = entry.getValue().size();
            } else {
                if(previousSet == 2) {
                    return entry.getValue().size() == 3;
                }
            }

        }

        return false;
    }

    public static boolean isStraightFlush(Hand hand) {
        return isStraight(hand) && isFlush(hand);
    }


}