1、random.nextInt(num)
public static void main(String args[]) {
Random rdom = new Random();
int max = 1314;
int min = 520;
for(int i = 0;i<2000;i++){
int count = rdom.nextInt((max - min + 1)) + min;
if(count==1313){
System.out.println("1313=================>>>"+count);
}else if (count==520){
System.out.println("520=================>>>"+count);
}else if(count<520 || count>1313){
System.out.println("error=================>>>"+count);
}else{
System.out.println("success=================>>>"+count);
}
}
}