下面这段代码，要如何优化算法才能让V开头的都优先到最上面呢？

package src;import java.lang.constant.Constable;import java.util.Comparator;import java.util.Objects;import java.util.PriorityQueue;import java.util.Queue;public class PriorityQueueTest {
    public static void main(String[] args) {
        Queue<User> q = new PriorityQueue<>(new UserComparator());        // 添加3个元素到队列:        q.offer(new User("Bossss", "A120"));        q.offer(new User("Bob", "A10"));        q.offer(new User("Alice", "A2"));        q.offer(new User("Alicess", "v10"));        q.offer(new User("Boss", "V1"));        System.out.println(q.poll()); // Boss/V1        System.out.println(q.poll()); // Bob/A1        System.out.println(q.poll()); // Alice/A2        System.out.println(q.poll()); // Alice/A2        System.out.println(q.poll()); // Alice/A2        System.out.println(q.poll()); // null,因为队列为空    }
}

class UserComparator implements Comparator<User> {
    public int compare(User u1, User u2) {

        if (u1.number.charAt(0) == u2.number.charAt(0)) {
            // 如果两人的号都是A开头或者都是V开头,比较号的大小:            Integer u1_int = Integer.parseInt(u1.number.substring(1));            Integer u2_int = Integer.parseInt(u2.number.substring(1));            return u1_int.compareTo(u2_int);        }

        if (u1.number.charAt(0) == 'V') {
            // u1的号码是V开头,优先级高:            return -1;        } else {
            return 1;        }
    }
}

//class User implements Comparable {class User {
    public final String name;    public final String number;    public User(String name, String number) {
        this.name = name;        this.number = number;    }

    public String toString() {
        return name + "/" + number;    }

//    @Override//    public int compareTo(Object o )//    {//        User u = (User) o;//        if (this.number.charAt(0) == u.number.charAt(0))//        {//            return Integer.parseInt(this.number.substring(1)) < Integer.parseInt(u.number.substring(1)) ? -1 : 1;//        }////        if (this.number.charAt(0) == 'V')//        {//            return -1;//        }//        else//        {//            return 1;//        }//    }}