在数组中存储非重复数字

Question

概述:我的程序必须在数组中存储20个非重复的随机生成的数字,范围为1到100.问题:如果我在内部for循环中找到匹配项(重复的#),我会标记布尔变量.这是我不知道该怎么做.在for循环之后,如果没有标记布尔值,我想将随机数添加到数组中.我还想增加x(直到我存储了20个非重复数字),但前提是我将元素添加到数组中.

public void duplication(){
    int max = 100; // max value for range
    int min = 1; // min value for range
    boolean duplicate = false;
    Random rand = new Random();

    for (int x = 0; x < 20; x++){
        //initiates array that stores 20 values
        int[] all = new int[20];
        //generates # from 1-100
        int randomNum = rand.nextInt((max - min) + 1) + min;
        all[x] = randomNum;
        //iterates through array
        for (int i : all) {
            //if there's a match (duplicate) flag boolean
            if (i == randomNum){
                duplicate = true;
            }
            else {
                duplicate = false;
            }
        }
    }
    //if boolean hasn't been flagged
    if (duplicate=false){
        //store to array
    }
}   

Answer 1

这将为您提供0到100之间的随机整数数组

public static void main(String[] args) {
    Set<Integer> s = new HashSet<Integer>(); // create a set
    Random r = new Random();
    while (s.size() < 20) {
        s.add(r.nextInt(100)+1);  // add elements to set upto size =20
    }
    Integer[] array = new Integer[20];
    s.toArray(array); // convert set to array of Integers
    System.out.println(Arrays.toString(array));

}

O/P:

[68, 69, 64, 65, 66, 67, 47, 74, 14, 17, 16, 21, 81, 54, 52, 82, 59, 57, 63, 88]