language:
- en
license: apache-2.0
size_categories:
- 100K<n<1M
task_categories:
- text-generation
pretty_name: Coding Interview SFT (100K)
tags:
- coding-interview
- algorithms
- data-structures
- system-design
- leetcode
- python
- software-engineering
- education
- technical-interview
- sft
- supervised-fine-tuning
- synthetic
configs:
- config_name: default
data_files:
- split: train
path: coding-interview-sft-100k.jsonl
Coding Interview SFT (100K)
100,000 ShareGPT conversations demonstrating expert-level coding interview preparation across algorithms, data structures, system design, and behavioral questions. Each example provides a complete solution with detailed explanation of the approach, step-by-step reasoning, time/space complexity analysis, and edge case handling.
Motivation
Coding interview preparation is one of the highest-demand AI assistant use cases. Models commonly fail by:
- Giving the solution without explaining the intuition: The reader gets code but doesn't understand why this approach works
- Skipping the "why not brute force": Not explaining why an O(n²) approach is insufficient and what insight enables the O(n log n) solution
- Missing edge cases: Solutions that fail on empty input, single elements, or duplicate values
- Wrong complexity analysis: Claiming O(n) for an O(n log k) algorithm, or missing the space complexity
- No pattern recognition: Not connecting the problem to the underlying pattern (sliding window, monotonic stack, two pointers, etc.)
- Inadequate behavioral question answers: Vague stories without STAR structure or concrete outcomes
This dataset trains models to teach coding interviews at the level of an experienced mentor — not just providing correct answers, but building the candidate's understanding of why the solution works.
Dataset Description
100,000 conversations across 7 problem categories and 3 difficulty levels:
Problem Categories
| Category | Examples |
|---|---|
arrays_hashing |
Two Sum, Group Anagrams, Top K Frequent |
two_pointers |
Container With Most Water, 3Sum, Trapping Rain Water |
sliding_window |
Longest Substring Without Repeating Characters, Minimum Window Substring |
binary_search |
Search in Rotated Sorted Array, Koko Eating Bananas |
dynamic_programming |
Coin Change, LIS, Edit Distance, Knapsack |
trees |
Level Order Traversal, Diameter, Lowest Common Ancestor |
graphs |
Number of Islands, Course Schedule, Dijkstra's |
heap_priority_queue |
Top K Frequent, Merge K Sorted Lists, Task Scheduler |
stack_queue |
Daily Temperatures, Valid Parentheses, Monotonic Stack |
linked_list |
Reverse Linked List, Merge Sorted Lists, Detect Cycle |
backtracking |
Subsets, Permutations, Combination Sum |
system_design |
URL Shortener, Rate Limiter, Notification System |
behavioral |
Disagreement with manager, Significant mistakes, Leadership |
Difficulty Distribution
easy: ~25% — foundational problems with clear patternsmedium: ~60% — the core of FAANG interviewshard: ~15% — advanced algorithms and system design
Format
{
"conversations": [
{
"from": "human",
"value": "**Two Sum** (Easy)\n\nGiven an array of integers `nums` and an integer `target`...\n\nPlease provide a solution in python with a clear explanation..."
},
{
"from": "gpt",
"value": "```python\ndef twoSum(nums, target):\n seen = {}\n for i, num in enumerate(nums):\n ...\n```\n\n**Approach: Hash Map (One Pass)**\n\nThe brute-force approach checks every pair in O(n²)..."
}
],
"metadata": {
"category": "arrays_hashing",
"difficulty": "easy",
"language": "python",
"title": "Two Sum"
},
"id": "abc123"
}
Key Properties of Responses
1. Pattern identification before code: Every algorithmic response names the underlying pattern (sliding window, monotonic stack, BFS, etc.) and explains why this pattern applies to this problem.
2. Brute force → optimization path: Responses acknowledge the naive approach and explain the insight that enables a better solution — building the candidate's problem-solving intuition.
3. Step-by-step trace: Complex algorithms include a worked example tracing through the algorithm on a concrete input.
4. Edge cases explicitly addressed: Empty input, single elements, all-same elements, overflow conditions — named and handled.
5. Complexity analysis with justification: Not just "O(n)" but why — which operation is O(n) and how the algorithm avoids doing it more than necessary.
6. Multiple approaches where relevant: Many problems include both the clean main solution and a notable alternative (recursive vs. iterative, sorting vs. hash map, DP vs. greedy).
7. System design depth: System design problems include API design, data modeling, architecture diagrams, scaling decisions, and specific trade-off analysis — not just high-level overviews.
8. Behavioral STAR format: Behavioral questions include a model answer with Situation/Task/Action/Result structure, common mistakes to avoid, and follow-up questions to prepare for.
Use Cases
- SFT fine-tuning for AI coding interview prep tools (AlgoExpert, LeetCode AI, Pramp)
- Training AI tutors for software engineering education
- Building AI interview coaches for bootcamps and universities
- Improving model performance on algorithmic reasoning benchmarks
- Training models for technical mentorship platforms
- Fine-tuning models for developer education and upskilling applications
License
Apache 2.0