[英]How do you have java create a random number within two ranges (e.g. 5-10 and 12-17)
I need to create a random number within two ranges, but I do not know how.我需要在两个范围内创建一个随机数,但我不知道如何。 Could someone help me?有人可以帮助我吗?
random numbers are generated between 0-1.随机数在 0-1 之间生成。 let's make numbers<0.5 5-10 and numbers > 0.5 12-17 by simply multiplying them.让我们通过简单地将它们相乘来使 numbers<0.5 5-10 和 numbers > 0.5 12-17 。
Try this :-尝试这个 :-
class PickRandomFromRange
{
private final List<Integer> range = new ArrayList<>();
final void addRange(int min, int max)
{
for(int i = min; i <= max; i++)
{
this.range.add(i);
}
}
int getRandom()
{
return this.range.get(new Random().nextInt(this.range.size()));
}
public static void main(String[] args)
{
PickRandomFromRange rir = new PickRandomFromRange();
rir.addRange(5,10);
rir.addRange(12,17);
System.out.println(rir.getRandom());
}
}
The above code will basically just makes a list of all the numbers which are in the ranges you give it, then picks a random number from that list, which is therefore a random number from any of the ranges.上面的代码基本上只是列出你给它的范围内的所有数字,然后从该列表中选择一个随机数,因此它是来自任何范围的随机数。
I figured out a way, although, I don't know if it is an efficient way of solving my problem.我想出了一个方法,虽然,我不知道这是否是解决我问题的有效方法。
if(userInput == 4){
charNumber = 48+random.nextInt(76);
if(charNumber>47 && charNumber<58){
outputFile.print((char)charNumber);
counter++;
}
if(charNumber>64 && charNumber<91){
outputFile.print((char)charNumber);
counter++;
}
if(charNumber>90 && charNumber<97){
outputFile.print((char)charNumber);
counter++
}
if(charNumber>96 && charNumber<123){
outputFile.print((char)charNumber);
counter++;
}
}
The ranges 5-10 and 12-17 give you a total of 6 + 6 = 12 possible selections.范围 5-10 和 12-17 为您提供总共 6 + 6 = 12 种可能的选择。
Pick a random number from 5 to 16. If the number is 11 or more then add one to it.从 5 到 16 中选择一个随机数。如果该数为 11 或更多,则向其加一。 Adding one effectively inserts the gap in your split range.添加一个有效地在您的拆分范围中插入间隙。
Random myRand = new Random();
// Number in range [5 .. 16].
int num = 5 + myRand.nextInt(17);
// Increase numbers beyond the gap.
if (num >= 11) {
num += 1;
}
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.