• insertHead, which puts a new Dog at the head of the list,

• insertTail, which puts a new Dog at the tail of the list

• weightDiff, which returns the difference between the weights of the heaviest and the lightest Dog in the list. A sled dog team is more effective if all the dogs in it have close to the same weight.

public class LLDogNode {

private Dog contents;

private LLDogNode link;

public LLDogNode (Dog dog, LLDogNode link) {

this.contents = dog;

this.link = link;

}

public Dog getContents() {

return contents;

}

public LLDogNode getLink() {

return link;

}

public void setContents(Dog dog) {

contents = dog;

}

public void setLink (LLDogNode link) {

this.link = link;

}

}

public class DogTeam {

private LLDogNode head;

public DogTeam(Dog dog) {

head = new LLDogNode(dog, null);

}

public void printTeam() {

LLDogNode cur = head;

int dogNumber = 1;

System.out.println("----------------");

while (cur != null) {

System.out.println(dogNumber + ". " + cur.getContents().getName() +

", " + cur.getContents().getWeight());

cur = cur.getLink();

dogNumber += 1;

}

}

public static void main(String[] args) {

DogTeam team = new DogTeam(new Dog("dog1", 60));

team.printTeam();

System.out.println("weightDiff: " + team.weightDiff());

team.insertTail(new Dog("dog0", 5));

team.insertHead(new Dog("dog2", 90));

team.printTeam();

System.out.println("weightDiff: " + team.weightDiff());

team.insertHead(new Dog("dog3", 7));

team.insertAfter(new Dog("dog4", 100), "dog2");

team.printTeam();

team.insertTail(new Dog("dog10", 205));

team.insertAfter(new Dog("dog9", 75), "dog10");

team.printTeam();

System.out.println("weightDiff: " + team.weightDiff());

}

public void insertHead(Dog dog) {

// TODO(0)

// puts new node containing dog at the head of the list

}

public void insertTail(Dog dog) {

// TODO(1)

// puts new node containing dog at the tail of the list

}

public double weightDiff() {

// TODO(2)

// returns difference between max and min weights of dogs in list

// pre: this list contains at least one node

return 0.0;

}

public void insertAfter(Dog dog, String dogName) {

}

}