java实现随机输出300题四则运算

package demo;import java.util.Random;public class math {  public static void main(String[] args) {    String[] operate=new String[]{"+","-","×","÷"};      int[] numbers=new int[1000];      for(int i=1;i<=1000;i++){      numbers[i-1]=i;    }     Random r=new Random();     for(int i=0;i<300;i++){       System.out.println(numbers[r.nextInt(1000)]+operate[r.nextInt(4)]+numbers[r.nextInt(1000)]+"=");    }   }   }