Java 数组算法，将 shuffle 类型从 "in-shuffle"交换到 "out-shuffle"时出错

Question

我正在尝试复制以下 while 循环，但它们交错我的“卡片”的方式有所不同。

这是我当前有效的 while 循环，我的目标是重新创建此循环，但颠倒两个 card_force 数组的顺序:

while (index >= 0) {

        card_force[index--] = bottom_half[j--];
        card_force[index--] = top_half[i--];
}

这是我想要制作的 while 循环:

while (index >= 0) {
        card_force[index--] = top_half[i--];    
        card_force[index--] = bottom_half[j--];

}

但是，如果两个循环都存在，则原始循环可以工作，但第二个 while 循环根本不工作，导致 52 行返回“null”。我需要它返回卡 27，然后返回卡 1，然后返回卡 26，然后返回卡 2，依此类推。

我在看似简单的修复过程中遇到了巨大的麻烦。

这是我当前的代码:

        String[] card_force = new String[52];
        String[] card_force2 = new String[52];
        int i = top_half.length - 1;
        int j = bottom_half.length - 1;
        int index = 51;


        // Card out shuffle
        while (index >= 0) {

        card_force[index--] = bottom_half[j--];
        card_force[index--] = top_half[i--];  
        }
        // Card in shuffle
        while (index >= 0) {
        card_force2[index--] = top_half[i--];
       card_force2[index--] = bottom_half[j--];
        }


        // Card out shuffle print
        System.out.println("\nCard Shuffle:\n");
        for (String card_force1 : card_force) {
           System.out.println(card_force1);
        }


        // Card in shuffle print
        for (String card_force1 : card_force2) {
           System.out.println(card_force1);
        }


}

当代码运行时，它返回以下结果:

Card Shuffle:

Card number 1: King of Clubs
Card number 27: 10 of Spades
Card number 2: Jack of Clubs
Card number 28: King of Diamonds
Card number 3: 6 of Diamonds
Card number 29: 5 of Diamonds
Card number 4: Queen of Hearts
Card number 30: 4 of Hearts
Card number 5: 5 of Clubs
Card number 31: Queen of Diamonds
Card number 6: Ace of Hearts
Card number 32: 7 of Diamonds
Card number 7: 3 of Hearts
Card number 33: 9 of Hearts
Card number 8: 2 of Hearts
Card number 34: 10 of Diamonds
Card number 9: 10 of Clubs
Card number 35: Jack of Diamonds
Card number 10: 2 of Spades
Card number 36: 2 of Diamonds
Card number 11: 9 of Clubs
Card number 37: 2 of Clubs
Card number 12: 8 of Spades
Card number 38: 4 of Spades
Card number 13: 7 of Spades
Card number 39: Ace of Diamonds
Card number 14: 8 of Clubs
Card number 40: 9 of Spades
Card number 15: Jack of Hearts
Card number 41: 6 of Clubs
Card number 16: 3 of Diamonds
Card number 42: 7 of Hearts
Card number 17: 6 of Hearts
Card number 43: King of Hearts
Card number 18: 4 of Clubs
Card number 44: Ace of Clubs
Card number 19: 3 of Spades
Card number 45: 8 of Hearts
Card number 20: Ace of Spades
Card number 46: 5 of Hearts
Card number 21: 10 of Hearts
Card number 47: Jack of Spades
Card number 22: Queen of Clubs
Card number 48: 9 of Diamonds
Card number 23: Queen of Spades
Card number 49: 8 of Diamonds
Card number 24: 7 of Clubs
Card number 50: 5 of Spades
Card number 25: 4 of Diamonds
Card number 51: 6 of Spades
Card number 26: King of Spades
Card number 52: 3 of Clubs
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Answer 1

您需要在第二次循环之前重置index的值。当 index 为 -1 时，第一个循环停止，并且当第二个循环检查该值时，该值仍然相同。结果，第二个循环甚至永远不会运行。