Question

java编程 随机交换数组元素

假如我有一个数组a[6]=(1,2,3,4,5,6),我想随机交换数组中的两个元素，应该怎么写？

Answer 1

import java.util.Random;

public class Test1111 {
public static void main(String[]args){
int flag = 0;
int []a={1,2,3,4,5,6};
Random rand = new Random();
int place_1 = rand.nextInt(6);
int place_2 = rand.nextInt(6);
while(true){
if(place_1 != place_2){
break;
}
}
flag = a[place_1];
a[place_1] = a[place_2];
a[place_2] = flag ;

for (int i = 0; i < a.length; i++) {
System.out.print(a[i]);
}

}

}

没做优化，大概就这样的

Answer 2

import java.util.Random;

public class RandomArray
{
public static void main(String[] args)
{
int[] a = {1,2,3,4,5,6,7,8,9};
Random random = new Random();
int ran = random.nextInt(a.length);
int ran2 = 0;
while (true)
{
ran2 = random.nextInt(a.length);
if (ran2 != ran)
{
break;
}
}
int i = a[ran];
a[ran] = a[ran2];
a[ran2]= i;
for (int j : a)
{
System.out.print(j);
}
}
}