java - 链接列表 - 如何制作一个递归添加方法来添加 "sort "？

Question

您好，我正在创建自己的链接列表，但没有实现 java.util.linkedlist

我想创建递归添加方法:

• 应该添加一个等级介于低等级和高等级之间的宝可梦像这样的事情:

妙蛙种子(5) -> 杰尼龟(15) -> 小火龙(20)

然后添加等级为6的(Pigeon):

妙蛙种子(5) -> 鸽子(6) -> 杰尼龟(15) -> 小火龙(20)

添加鸽子是我苦苦挣扎的部分

到目前为止，我已经成功地对它们进行了排序，因为我一直将它们从最小到最大添加:

d1.addPokemon(p1);//5 级

d1.addPokemon(p2);//15 级

d1.addPokemon(p3);//20级

d1.addPokemon(p4);//level 6 - 不添加，我的方法有问题我不知道要更改什么

谢谢

        public class Trainer{

            public final String name;
            private Pokeball head;

            public Trainer(String name) {
                this.name = name;
            }

            public void display() {
                System.out.print(this.name + " : ");
                this.head.display();
            }

            public void addPokemon(Pokemon pok) {
                if (this.head != null) {
                    this.head.addPokemon(this.head, pok);
                } else {
                    this.head = new Pokeball(pok);
                }
            }

        }

        public class Pokeball {

            private Pokemon pok;
            private Pokeball next;

            public Pokeball(Pokemon pok) {
                this.pok = pok;
            }

  public Pokeball addPokemon(Pokeball current, Pokemon pok) {

        if (current == null) {
            return null;
        }
        if (current.pok.getLevel() > pok.getLevel()) {
            Pokeball newPokeball = new Pokeball(pok);
            newPokeball.next = current;
            return newPokeball;
        }
        // if next is null add it to next
        if (current.next == null) {
            current.next = new Pokeball(pok);
        }
        // if next is not null and value is between two sequences add it between
        else if (pok.getLevel() > current.pok.getLevel() && pok.getLevel() <= current.next.pok.getLevel()) {
            Pokeball newPokeball = new Pokeball(pok);
            newPokeball.next = current.next;
            current.next = newPokeball;
        }
        // If value is not between call recursion again
        else {
            addPokemon(current.next, pok);

        }
        return current;
    }
        public class Pokemon {

            private String name;
            private int level;

            public Pokemon(String name, int level) {
                this.name = name;
                this.level = level;

            }

            public void display() {
                System.out.println();
                System.out.print(this.name + " : " + this.level);

            }

            public String getName() {
                return name;
            }

            public void setName(String name) {
                this.name = name;
            }

            public int getLevel() {
                return level;
            }

            public void setLevel(int level) {
                this.level = level;
            }

        }

        public class test {
            public static void main(String[] args) {

                Pokemon p1 = new Pokemon("Bulbasaur", 5);
                Pokemon p2 = new Pokemon("Squirtle", 15);
                Pokemon p3 = new Pokemon("Charmander", 20);
                Pokemon p4 = new Pokemon("Pigeon", 6);

                Trainer t1 = new Trainer("Pierre");
                t1.addPokemon(p1);
                t1.addPokemon(p2);
                t1.addPokemon(p3);
                t1.addPokemon(p4);

                t1.display();

        // prints :
        Pierre : 
        Bulbasaur : 5 
        Squirtle : 15 
        Charmander : 20 
    // But pigeon is not here ! :(

            }

        }

Answer 1

像这样更改 Pokeball 类中的 addPokemon 方法。

 public void addPokemon(Pokeball current, Pokemon pok) {
     // if next is null add it to next
     if (current.next == null){
         current.next = new Pokeball(pok); 
     }
    // if next is not null and value is between two sequences add it between
    else if( pok.getLevel() > current.pok.getLevel() && pok.getLevel()<= 
    current.next.pok.getLevel()) {
       Pokeball newPokeball =  new Pokeball(pok);  
       newPokeball.next = current.next;
       current.next = newPokeball;
    } 
  // If value is not between call recursion again
   else {
      addPokemon(current.next, pok);
   }

}

在 Trainer 类中更改 addPokemon 方法；

 public void addPokemon(Pokemon pok) {
        if (this.head != null) {
            if(pok.getLevel()<this.head.pok.getLevel()){
                Pokeball newPokeball = new Pokeball(pok);
                newPokeball.next = this.head;
                this.head = newPokeball;
                return;
            }
            this.head.addPokemon(this.head, pok);
        } else {
            this.head = new Pokeball(pok);
        }
    }