标题翻译
Generate an amount of random numbers from a paramter then store them to call in a method later
问题
我正在尝试生成随机数字，数量由一个参数确定，然后存储这些数字，以便我可以将它们分配给一个唯一的 ID 字段，与一个字符串代码相结合，例如用户输入代码 "HG-" 和数字 4，该方法将输出 HG-3981 或 HG-8394 等。
我的尝试：
public void generateCustomerID(String prefix, int length)
{
for (int i = 0; i == length; i++)
{
Random random = new Random();
int rand = random.nextInt((9 - 1) + 1) + 1;
}
System.out.println(prefix + "-" + length);
}
英文翻译
I am trying to generate random numbers the amount determined by a paramter then store these numbers so i can assign them to a uniqe id field combined with a string code before e.g user inputs code "HG-" and the number 4 the method will output HG-3981 or HG-8394 etc
My attempt
{
for (int i = 0; i == length; i++)
{
Random random = new Random();
int rand = random.nextInt((9 - 1) + 1) + 1;
}
System.out.println(prefix + "-" + length);
}
</details>
# 答案1
**得分**: 0
Sure, here's the translation:
不应该打印 `length`，你应该打印 `rand` 变量。
*示例：*
```java
System.out.println(prefix + "-" + rand);
希望这有所帮助！
英文翻译
Instead of printing the length, shouldn't you be printing the rand variable?
Example:
System.out.println(prefix+"-"+rand);
Hope this helped!
答案2
得分: 0
这将生成以 0 填充的长度为 length 的数字整数：
Random rand = new Random();
int length = 6;
DecimalFormat df = new DecimalFormat();
df.setMaximumIntegerDigits(length);
df.setMinimumIntegerDigits(length);
df.setGroupingUsed(false);
for (int i = 0; i < 50; i++) {
System.out.println(df.format(rand.nextInt((int)Math.pow(10,length))));
}
您需要存储这些数字以确保唯一性。
您可以使用以下任意一种方式来记录已生成的数字：Set<Integer>、int[10^length]、boolean[10^length] 或 BitSet(10^lenght)。请注意进程重启等情况。
英文翻译
This will generate 0 padded length digit integers:
Random rand = new Random();
int length = 6;
DecimalFormat df = new DecimalFormat();
df.setMaximumIntegerDigits(length);
df.setMinimumIntegerDigits(length);
df.setGroupingUsed(false);
for (int i = 0; i < 50; i++) {
System.out.println(df.format(rand.nextInt((int)Math.pow(10,length))));
}
You will have to store these in order to ensure uniqueness.
You can use any of Set<Integer>, int[10^length], boolean[10^length] or BitSet(10^lenght) in order to record already generated numbers. Be mindful of process restarts etc.
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