Count minimum cost in linked list
Last updated: January 24, 2026
Quick Overview
Given a singly linked list where each node contains a cost associated with it, write a function to calculate the minimum total cost to traverse the entire list from the head to the tail. The function should take the head of the linked list as input and return an integer representing the minimum cost.
Cloudflare
January 24, 202684
5
4,040 solved
Given a singly linked list where each node contains a cost associated with it, write a function to calculate the minimum total cost to traverse the entire list from the head to the tail. The function should take the head of the linked list as input and return an integer representing the minimum cost.
Cloudflare uses this problem in the Phone Screen to evaluate your algorithmic thinking. They expect you to discuss multiple approaches, analyze trade-offs between them, and implement the optimal solution with clean, readable code.
What the Interviewer Expects
- Identify the correct data structure and algorithm for the problem
- Write clean, bug-free code with proper variable naming
- Analyze time and space complexity correctly
- Handle basic edge cases (empty input, single element)
- Communicate your thought process while coding
Key Topics to Cover
How to Approach This
- Clarify input constraints and edge cases before writing code.
- Walk through your approach verbally and confirm with the interviewer before coding.
- Start with a brute force solution, then optimize. Mention time and space complexity.
- Test your solution with examples, including edge cases like empty input or duplicates.
- Consider common patterns: sliding window, two pointers, hash map, BFS/DFS, dynamic programming.
Possible Follow-up Questions
- What is the worst-case input for your solution?
- How would you modify your solution to handle streaming input?
- Can you solve this iteratively instead of recursively (or vice versa)?
Sharpen Your Skills on Codemia
Practice similar problems with our interactive workspace, get AI feedback, and track your progress.
Practice DSA ProblemsSample Answer
Problem Analysis
The problem requires us to traverse a singly linked list and calculate the total cost associated with each node. The traversal is linear, moving from the head to the tail of the list, and we need to s...
Approach
- Initialize a variable
total_costto 0 to store the cumulative cost. - Create a pointer
currentthat starts at the head of the linked list. - While
currentis not null:- Add the cost of ...
Submit Your Answer
