Please make search method to find the the highest value in the linked list and then output the highest value

Go through the double-ended doubly-linked list to find the largest int value held in any of the links. If the doubly-linked list is empty or defective in any way, return 0.

I have most of the code written.

Please write the search() method which reports to the main method. 

 

There is no input

 

Use java programming language

 

package linkedList;

import java.util.*;

 

public class Main {

public static void main(String args[] ) throws Exception {

Scanner myscanner = new Scanner(System.in);

int num = Integer.parseInt(myscanner.nextLine());

Link[] array = new Link[num];

for(int i=0;i

array[i]=new Link(Integer.parseInt(myscanner.nextLine()));

}

while(myscanner.hasNext()){

int select=myscanner.nextInt();

int previous=myscanner.nextInt();

int next=myscanner.nextInt();

if(previous!=-1){

array[select].previous=array[previous];

}

if(next!=-1){

array[select].next=array[next];

}

}

LinkedList mylist = new LinkedList();

if(num>0){

mylist.first=array[0];

mylist.last=array[num-1];

}

 

System.out.println(search(mylist));

 

}

 

//don't edit the code above, only edit the search method below

 

public static int search(LinkedList mylist){

/* return the highest value held in any of the links, 0 if defective or empty*/

 

 

      return 0;

}

 

//don't edit the code below, only edit the search method above

 

}

 

class Link{

  public int data;

  public Link next;

  public Link previous;

 

public Link(int input){

data=input;

next=null;

previous=null;

}

}

 

class LinkedList {

  public Link first;

public Link last;

 

  public LinkedList( ){

    first=null;

last=null;

  }

 

  public boolean isEmpty( ){

    return (first==null);

  }

 

public void insertHead(Link insert){

if(isEmpty()){

first=insert;

last=insert;

}else{

first.previous=insert;

insert.next=first;

first=insert;

}

}

}

required search method would be

public static int search(LinkedList mylist) {


		/* return the highest value held in any of the links, 0 if defective or empty */
		
		int max = Integer.MIN_VALUE;
		
		//if list empty
		if(mylist.isEmpty())
			return 0;
		
		Link curr = mylist.first;
		
		while(curr!= mylist.last) {
			
			//if defective
			if(curr.data==-1)
				return 0;
			
			if(curr.data>max)
				max = curr.data;
			
			curr = curr.next;
		}


		if(curr.data>max)
			max = curr.data;


		return max;


	}

Complete code would be

Step-by-step explanation

Main.java

package linkedList;

import java.util.*;


public class Main {


	public static void main(String args[]) throws Exception {


		Scanner myscanner = new Scanner(System.in);


		int num = Integer.parseInt(myscanner.nextLine());


		Link[] array = new Link[num];


		for (int i = 0; i < num; i++) {


			array[i] = new Link(Integer.parseInt(myscanner.nextLine()));


		}
		
		System.out.println("end link");


		int i =0;
		while (myscanner.hasNext()) {


			System.out.println("link : "+i++);
			int select = myscanner.nextInt();


			int previous = myscanner.nextInt();


			int next = myscanner.nextInt();


			if (previous != -1) {


				array[select].previous = array[previous];


			}


			if (next != -1) {


				array[select].next = array[next];


			}


		}


		LinkedList mylist = new LinkedList();


		if (num > 0) {


			mylist.first = array[0];


			mylist.last = array[num - 1];


		}


		System.out.println(search(mylist));


	}


//don't edit the code above, only edit the search method below


	public static int search(LinkedList mylist) {


		/* return the highest value held in any of the links, 0 if defective or empty */
		
		int max = Integer.MIN_VALUE;
		
		//if list empty
		if(mylist.isEmpty())
			return 0;
		
		Link curr = mylist.first;
		
		while(curr!= mylist.last) {
			
			//if defective
			if(curr.data==-1)
				return 0;
			
			if(curr.data>max)
				max = curr.data;
			
			curr = curr.next;
		}


		if(curr.data>max)
			max = curr.data;


		return max;


	}


//don't edit the code below, only edit the search method above


}


class Link {


	public int data;


	public Link next;


	public Link previous;


	public Link(int input) {


		data = input;


		next = null;


		previous = null;


	}


}


class LinkedList {


	public Link first;


	public Link last;


	public LinkedList() {


		first = null;


		last = null;


	}


	public boolean isEmpty() {


		return (first == null);


	}


	public void insertHead(Link insert) {


		if (isEmpty()) {


			first = insert;


			last = insert;


		} else {


			first.previous = insert;


			insert.next = first;


			first = insert;


		}


	}


}