Question

JAVA - Write a function in your Main class LinkedList<E> mergeLists(LinkedList<E> list1, LinkedList<E> list2) - given two ordered linked lists of integers, merge the two lists into a single LinkedList whose elements are in sorted order. You should create a new LinkedList and add the values from list1 and list2 into the new list in sorted order. Do not modify list1 or list 2.

1. list1 => 1 -> 3 -> 7 -> 8, list2 => 2 -> 5 -> 7 -> 10, returns 1 -> 2 -> 3 -> 7 -> 7 -> 8 -> 10

Answer 1

import java.util.Arrays;
import java.util.LinkedList;

public class MergeLinkedLists {

    static <E extends Comparable<E>> LinkedList<E> mergeLists(LinkedList<E> list1, LinkedList<E> list2) {
        LinkedList<E> result = new LinkedList<>();
        int i = 0, j = 0;
        while (i <list1.size() || j < list2.size()) {
            if (j >= list2.size() || (i < list1.size() && list1.get(i).compareTo(list2.get(j)) < 0)) {
                result.add(list1.get(i++));
            } else {
                result.add(list2.get(j++));
            }
        }
        return result;
    }

    public static void main(String[] args) {
        LinkedList<Integer> list1 = new LinkedList<>(Arrays.asList(1, 3, 7, 8));
        LinkedList<Integer> list2= new LinkedList<>(Arrays.asList(2, 5, 7, 10));
        System.out.println(mergeLists(list1, list2));
    }
}