Good evening! Here's our prompt for today.

Write an algorithm to merge two sorted linked lists and return it as a new sorted list. The new list should be constructed by joining the nodes of the input lists.

You may assume the following node definition:

1class Node:
2    def __init__(self, val):
3        self.value = val
4        self.next = None
5
6list1 = Node(1)
7list1.next = Node(2)
8
9print(list1.value, '->', list1.next.value)

Write a method called mergeSortedLists that would be invoked as such in the following example:

1# List 1: list1 = [1, 5, 6]
2# List 2: list2 = [2, 3, 4]
3
4merged_list = merge_sorted_lists(list1, list2)
5# Output: [1, 2, 3, 4, 5, 6]

As you can see, the linked lists are merged in an ascending sorted order.

Constraints

• Length of the linked lists <= 100000
• The values in the nodes will be in the range -1000000000 and 1000000000
• Expected time complexity : O(n)
• Expected space complexity : O(n) considering the call stack in recursion

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​

def merge_sorted_lists(head1, head2):

    # fill in

    return head1

​

​

# Node definition

class Node:

    def __init__(self, val):

        self.val = val

        self.next = None

​

​

def create_nodes(head, nodes):

    for val in nodes:

        new_node = Node(val)

        head.next = new_node

        head = new_node

​

​

list1 = Node(3)

nodes1 = [4, 5, 6, 7, 8, 9, 10]

create_nodes(list1, nodes1)

​

list2 = Node(1)

nodes2 = [2, 3, 4, 5, 6, 7, 8]

create_nodes(list2, nodes2)

​

​

def list_to_str(head):

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