如何在Java的一张卡片牌中初始化布尔阵列

Question

如何初始化一张卡片套装的布尔阵列，然后制成，以便随机数将西装变成true？为了初始化数组，我有

    boolean[] suitsSelected = {"spades","clubs","diamonds", "hearts"};

然后声明一个随机数

    Random myRandom = newRandom();
    int card = myRandom.nextInt(51);

选择卡一旦选择卡，然后将布尔套装变成true？

    spade = (card >= 0 && card < 14);
    heart = (card >= 14 && card < 27);
    club = (card >= 27 && card < 39);
    diamond = (card >= 40 && card < 52);

Answer 1

您可以使用布尔值，例如

final int SPADES_INDEX = 0;
final int CLUBS_INDEX = 1;
final int HEARTS_INDEX = 2;
final int DIAMONDS_INDEX = 3;
final boolean[] suits = new boolean[4];
// helper function
void switchToSuit(int suitIndex) {
    for(int i = 0; i < suits.length; i++) {
        suits[i] = (suitIndex == i);
    }
}
// later
if(card >= 0 && card <= 14) switchToSuit(SPADES_INDEX);

，但这有点奇怪。如果需要的话，您可以使用int的简单得多。

final int SPADES_INDEX = 0;
final int CLUBS_INDEX = 1;
final int HEARTS_INDEX = 2;
final int DIAMONDS_INDEX = 3;
int suit = card / 13; // 0-12 are 0, 13-25 are 1, 26-38 are 2, and 39-51 are 3

更好的方法是使用enum

import java.util.*; 
public class Main {
    static Random rand = new Random();
    static enum Suit {
        SPADES,
        CLUBS,
        HEARTS,
        DIAMONDS;
        public String toString() {
            return name().substring(0, 1);
        }
    }
    static enum Rank {
        ACE("A"), TWO("2"), THREE("3"), FOUR("4"),
            FIVE("5"), SIX("6"), SEVEN("7"), EIGHT("8"),
            NINE("9"), TEN("T"), JACK("J"), QUEEN("Q"), KING("K");
        final String key;
        Rank(String key) {
            this.key = key;
        }
        public String toString() {
            return key;
        }
    }
    public static void main(String[] args) {
        List <String> pocket = new ArrayList<>();
        List <String> board = new ArrayList<>();
        int[] deck = new int[52];
        for (int i = 0; i < 52; i++) {
            deck[i] = i;
        }
        shuffleArray(deck);
        for (int i = 0; i < 2; i++) {
            int card = deck[i];
            Suit suit = Suit.values()[card / 13];
            Rank rank = Rank.values()[card % 13];
            pocket.add("" + rank + suit);
        }
        for (int i = 0; i < 5; i++) {
            int card = deck[i + 2];
            Suit suit = Suit.values()[card / 13];
            Rank rank = Rank.values()[card % 13];
            board.add("" + rank + suit);
        }
        System.out.println("Hold'em pocket: " + pocket);
        System.out.println("Hold'em board: " + board);
    }
    // Fisher–Yates shuffle - https://stackoverflow.com/a/1520212/330057
    static void shuffleArray(int[] ar) {
        // If running on Java 6 or older, use `new Random()` on RHS here
        for (int i = ar.length - 1; i > 0; i--) {
            int index = rand.nextInt(i + 1);
            // Simple swap
            int a = ar[index];
            ar[index] = ar[i];
            ar[i] = a;
        }
    }
}