Java beetwen 1和90中的随机数

Question

如何使用Java中的Math.random（）使随机数beetwen 1和90成为随机数？

是否正确：

Math.random()*90+1;

Answer 1

import java.util.Scanner;

public class Test2 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("first bound   ");
        int fbound = scanner.nextInt();
        System.out.print("second bound:  ");
        int sbound = scanner.nextInt();
        if (fbound != sbound) {
            if (sbound > fbound) {
                int range = (sbound - fbound) + 1;// inclusive 2 bounds
                int ran = (int) (Math.random() * range) + fbound;// Math.random() method return double, but i do type casting
                System.out.println(ran);

            } else {
                fbound = fbound + sbound;// change two bounds value without third variable
                sbound = fbound - sbound;
                fbound = fbound - sbound;
                int range = (sbound - fbound) + 1;
                int ran = (int) (Math.random() * range) + fbound;
                System.out.println(ran);
            }
        } else {
            System.out.println("This incoming bound is wrong!!!!!!!!");
        }
        main(args);
    }
}

我为动态界线写书，同时您找到了不同的方式！

示例 ---> Math.random() explanation，https://programmerfriend.com/java-random-numbers/