如何在Java中随机化和随机排列数字数组？

How to randomize and shuffle array of numbers in Java?

首先，创建一个整数数组-

1	int[] arr = { 20, 40, 60, 80,100, 120, 140, 160, 180, 200};

现在，创建一个Random类对象-

1	Random rand = new Random();

循环直到数组的长度并随机播放元素-

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for (int i = 0; i < arr.length; ++i) {
int index = rand.nextInt(arr.length - i);
int tmp = arr[arr.length - 1 - i];
arr[arr.length - 1 - i] = arr[index];
arr[index] = tmp;
}

例

现场演示

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import java.util.Arrays;
import java.util.Random;
public class Demo {
public static void main(String[] args) {
int[] arr = { 20, 40, 60, 80,100, 120, 140, 160, 180, 200};
System.out.println("The integer array ="+Arrays.toString(arr));
Random rand = new Random();
for(int i = 0; i < arr.length; ++i) {
int index = rand.nextInt(arr.length - i);
int tmp = arr[arr.length - 1 - i];
arr[arr.length - 1 - i] = arr[index];
arr[index] = tmp;
}
System.out.println("Shuffle integer array ="+Arrays.toString(arr));
}
}

输出量

1 2	The integer array = [20, 40, 60, 80, 100, 120, 140, 160, 180, 200] Shuffle integer array = [160, 100, 20, 60, 140, 200, 120, 40, 80, 180]