Java 在两个数组中交换两个字符

我有两个字符数组和两个随机数，每个数组一个数字

我想得到第一个数组中随机数位置的字符，并将其与第二个数组中第二个随机数位置的字符交换。我试过这个：

char[] chs1 = {'h', 'e', 'l', 'l', 'o'};
char[] chs2 = {'w', 'o', 'r', 'l', 'd'};
Random rand = new Random();
int ranNum1 = rand.nextInt(chs1.length);
int ranNum2 = rand.nextInt(chs2.length);
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = chs1[ranNum1];

---

有人知道如何交换吗？

您需要一个临时变量来交换：

char temp = chs1[ranNum1];
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = temp;

---

您需要一个临时变量：

char temp = chs1[ranNum1];
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = temp;

char temp = chs2[ranNum2];
chs2[ranNum2] = chs1[ranNum1];
chs1[ranNum1] = temp;

public static void main(String[] argv) {
    char[] a1 = { 'h', 'e', 'l', 'l', 'o' };
    char[] a2 = { 'w', 'o', 'r', 'l', 'd' };
    Random rand = new Random();

    for (int n = 0; n < 2; n++) {
        int indexToSwap = rand.nextInt(a1.length);

        System.out.println("Swap " + indexToSwap);
        System.out.println("Before A1 " + toString(a1) + ", A2 " + toString(a2));

        a1[indexToSwap] ^= a2[indexToSwap];
        a2[indexToSwap] ^= a1[indexToSwap];
        a1[indexToSwap] ^= a2[indexToSwap];

        System.out.println(" After A1 " + toString(a1) + ", A2 " + toString(a2));
    }
}

private static String toString(char[] a) {
    StringBuilder sb = new StringBuilder();
    for (char c : a) {
        sb.append(", ").append(c);
    }
    return "[" + sb.toString().substring(1).trim() + "]";
}

---

使用临时变量：

char temp = chs1[ranNum1];
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = temp;

char temp = chs2[ranNum2];
chs2[ranNum2] = chs1[ranNum1];
chs1[ranNum1] = temp;

public static void main(String[] argv) {
    char[] a1 = { 'h', 'e', 'l', 'l', 'o' };
    char[] a2 = { 'w', 'o', 'r', 'l', 'd' };
    Random rand = new Random();

    for (int n = 0; n < 2; n++) {
        int indexToSwap = rand.nextInt(a1.length);

        System.out.println("Swap " + indexToSwap);
        System.out.println("Before A1 " + toString(a1) + ", A2 " + toString(a2));

        a1[indexToSwap] ^= a2[indexToSwap];
        a2[indexToSwap] ^= a1[indexToSwap];
        a1[indexToSwap] ^= a2[indexToSwap];

        System.out.println(" After A1 " + toString(a1) + ", A2 " + toString(a2));
    }
}

private static String toString(char[] a) {
    StringBuilder sb = new StringBuilder();
    for (char c : a) {
        sb.append(", ").append(c);
    }
    return "[" + sb.toString().substring(1).trim() + "]";
}

---

您所做的是更新一个值，然后获取更新后的值并将其重新放在原来的位置。

您应该在temp变量中至少存储一个字符，如下所示：

char tmp = chs1[ranNum1];
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = tmp;

---

这是行不通的：

chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = chs1[ranNum1];

这是因为在第一条语句的末尾，chs1[ranNum1]与chs2[ranNum2]相同；所以第二句话是否定的！i、 e.您已经丢失了chs[ranNum1]中原来的内容

您需要一个临时的：

char s = chs1[ranNum1];
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = s;

---

我想你应该试试冒泡排序算法

char[] chs1 = {'h', 'e', 'l', 'l', 'o'};
char[] chs2 = {'w', 'o', 'r', 'l', 'd'};
Random rand = new Random();
int ranNum1 = rand.nextInt(chs1.length);
int ranNum2 = rand.nextInt(chs2.length);
ch temp = chs1[ranNum1];
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = temp;

---

您需要一个临时字符来存储值。因为当你：chs1[ranNum1]=chs2[ranNum2]的时候，你失去了chs1[ranNum1]中的值

例如：

    chs1[ranNum1] = 'd'
    chs2[ranNum2] = 's'

分配完任务后，您将不再需要d。它还将指向s

那么在分配之后呢

chs1[ranNum1]=“s” chs2[ranNum2]=“s”

总而言之：

    char temp = chs1[ranNum1];
    chs1[ranNum1] = chs2[ranNum2];
    chs2[ranNum2] = temp;

---

只是为了好玩。。。肯定是上一个。解决方案可以工作，但这一解决方案在没有

temp

变量的情况下也可以执行相同的任务：

char temp = chs1[ranNum1];
chs1[ranNum1] = chs2[ranNum2];
chs2[ranNum2] = temp;

char temp = chs2[ranNum2];
chs2[ranNum2] = chs1[ranNum1];
chs1[ranNum1] = temp;

public static void main(String[] argv) {
    char[] a1 = { 'h', 'e', 'l', 'l', 'o' };
    char[] a2 = { 'w', 'o', 'r', 'l', 'd' };
    Random rand = new Random();

    for (int n = 0; n < 2; n++) {
        int indexToSwap = rand.nextInt(a1.length);

        System.out.println("Swap " + indexToSwap);
        System.out.println("Before A1 " + toString(a1) + ", A2 " + toString(a2));

        a1[indexToSwap] ^= a2[indexToSwap];
        a2[indexToSwap] ^= a1[indexToSwap];
        a1[indexToSwap] ^= a2[indexToSwap];

        System.out.println(" After A1 " + toString(a1) + ", A2 " + toString(a2));
    }
}

private static String toString(char[] a) {
    StringBuilder sb = new StringBuilder();
    for (char c : a) {
        sb.append(", ").append(c);
    }
    return "[" + sb.toString().substring(1).trim() + "]";
}