AskSia

Plus

Write Java code for this question: You are given the heads of two sorted linked ...

Mar 15, 2024

Write Java code for this question: You are given the heads of two sorted linked lists list1 and list2. Merge the two lists into one sorted list. The list should be made by splicing together the nodes of the first two lists. Return the head of the merged linked list.

java

Explanation

The provided Java code defines a ListNode class for the linked list nodes, a Solution class with a method to merge two sorted linked lists, and a Main class to test the mergeTwoLists method with two use cases. The printList helper function is used to print the linked list for visual verification.

Step-by-step Instruction

▪

Implement the mergeTwoLists method in the Solution class to merge two sorted linked lists

▪

Use a dummy node to simplify the merging process and handle edge cases

▪

Use a while loop to iterate through both lists until one is exhausted

▪

After the loop, connect the remaining part of the non-exhausted list to the merged list

▪

Return the merged list, which starts from the dummy node's next pointer

▪

In the Main class, create test cases to verify the correctness of the mergeTwoLists method

▪

Use the printList helper function to print the result of the merged lists for verification

Time Complexity

The time complexity is O(n + m), where n and m are the lengths of the two linked lists, because the algorithm must visit each element in both lists once.

Space Complexity

The space complexity is O(1), as the merge is done in-place and only a constant amount of extra space is used for the dummy node and pointers.