随机出题程序

package 编题程序;
import java.util.Random;
import java.util.Scanner;
public class 编题程xu {
           
        public static void main(String args[]) {
         System.out.println("请输入一页的题目数量:");
            Scanner input = new Scanner(System.in);
            int n = input.nextInt();
            int sum=1;
            System.out.println("第"+sum+"份");
            System.out.println("-----------------");
         for(int i = 0 ; i < n;i++) {
         int a = new Random().nextInt(100);//随机数a
            int b = new Random().nextInt(100);//随机数b
            int suijifu = new Random().nextInt(4);//随机运算符
     String symbol=" ";
        switch(suijifu) {
        case(0):
         symbol = "+";break;
        case(1):
         symbol = "-";break;
        case(2):
         symbol ="×";break;
        case(3):
        {  if(b==0) symbol = "+";
            if(a%b!=0) symbol = "-";
            if(a%b==0)symbol = "÷";
        }
        break;
        }
      
        System.out.println(a+" "+symbol+" "+b+"=");
     }
         System.out.println("-----------------");
         sum++;
  }
}