如何制作两个数组，在 Java 中随机化 10 到 30 和 11 和 30 之间的数字

Question

I have to make two arrays that randomizes numbers between 10 and 30(first array), 11 and 30(second array) in java. i'm supposed to fill the first and second one in numerical order... how? i haven't started yet and i need to be finished soon.

int[] a = new int[20];


    int random = (int)(Math.random()*21+10);

    for(int x=0; x<a.length; x++){ 



        System.out.print(random + " ");
    }

    System.out.println();

    for(int i=11; i<=30; i++){
        System.out.print(i + " ");

    }

}

}

Answer 1

you can use

((Math.random() * ((max - min) + 1)) + min) to get random with limit

int min = 10;
        int max = 30;
        int[] a = new int[20];
        int[] b = new int[20];
        for(int i =0;i<a.length;i++) {
            a[i]= (int) ((Math.random() * ((max - min) + 1)) + min);
        }
        max =  31;
        for(int i =0;i<b.length;i++) {
            b[i]= (int) ((Math.random() * ((max - min) + 1)) + min);
        }

this will do