java如何从100个数中随机获得若干个不重复的数

Answer 1

用随机对象，把100个数放在数组里面，通过 random.next(100)产生随机下标, 如果重复的，重新产生随机下标

Answer 2

import java.util.Arrays;

import java.util.HashSet;

import java.util.Random;

import java.util.Set;

public class Test {

public static void main(String[] args) {

int[] num = new int[100];

for (int i = 0; i < 100; i++) {

num[i] = i;

}

Integer[] result = getRandomNum(num, 10);

System.out.println(Arrays.toString(result));

}

public static Integer[] getRandomNum(int[] num, int n) {

Set<Integer> sets = new HashSet<Integer>();

Random random = new Random();

while (sets.size() < n) {

sets.add(random.nextInt(100));

}

return sets.toArray(new Integer[n]);

}

}