DEV Community

net programhelp
net programhelp

Posted on

How did I prepare to get the TikTok Offer in 2 weeks?

How I Landed a TikTok Offer in Just 2 Weeks (2025 Strategy)

Securing a TikTok software engineering (SWE) offer in two weeks required hyper-focused preparation, strategic prioritization, and efficient execution. Below is my step-by-step breakdown, including resources, daily schedule, and key insights that made it possible.


1. Understand TikTok’s Interview Process (2025 Updates)

TikTok’s hiring process consists of:

  1. Online Assessment (OA) – 2-3 coding questions (LeetCode Medium-Hard).
  2. Technical Phone Screen – 1 algorithm problem + behavioral questions.
  3. Virtual Onsite (4 Rounds) – Algorithms, System Design, Coding, and Behavioral.

Key Changes in 2025:

  • More graph and dynamic programming (DP) problems (e.g., social network analysis).
  • System design now includes real-time video processing (e.g., live-streaming optimizations).
  • Behavioral questions align with TikTok’s core values (e.g., "How do you handle rapid iteration?").

2. My 14-Day Preparation Plan

✅ Days 1-3: Master the Tiktok OA (Coding & Debugging)

Focus:

  • LeetCode Medium-Hard problems (TikTok’s top tags: #BFS, #DP, #Graph).
  • Debugging practice (common in OA1).

Key Problems I Solved:

  1. Shortest Path in Social Network (BFS)
   def shortest_path(graph, start, end):  
       from collections import deque  
       queue = deque([(start, [start])])  
       visited = set()  
       while queue:  
           node, path = queue.popleft()  
           if node == end:  
               return path  
           for neighbor in graph[node]:  
               if neighbor not in visited:  
                   visited.add(neighbor)  
                   queue.append((neighbor, path + [neighbor]))  
       return []  
Enter fullscreen mode Exit fullscreen mode
  1. Maximize Video Engagement (DP – Knapsack Variant)
  2. Detect Fake Accounts (Union-Find/Graph)

Resources Used:

  • LeetCode TikTok Tag (Link)
  • HackerRank OA Simulator (timed practice)

✅ Days 4-7: Crush the Technical Phone Screen

Focus:

  • Optimized coding under pressure (45-minute limit).
  • Clear verbal explanations (interviewers judge thought process).

Strategy:

  1. First 5 mins: Clarify edge cases (e.g., empty input, duplicates).
  2. Next 10 mins: Write brute-force solution.
  3. Last 15 mins: Optimize (e.g., memoization, sliding window).

Example Question from My Interview:

"Given a user’s watch history, find the longest sequence of videos from the same creator."

Solution:

def longest_creator_sequence(watch_history):  
    max_len = current_len = 1  
    for i in range(1, len(watch_history)):  
        if watch_history[i]["creator"] == watch_history[i-1]["creator"]:  
            current_len += 1  
            max_len = max(max_len, current_len)  
        else:  
            current_len = 1  
    return max_len  
Enter fullscreen mode Exit fullscreen mode

✅ Days 8-11: System Design Deep Dive

Focus:

  • Real-time systems (e.g., live comments, video feeds).
  • Scalability (10M+ concurrent users).

Structured Approach:

  1. Requirements (QPS, latency, consistency).
  2. APIs (REST vs. WebSockets).
  3. Database (SQL vs. NoSQL, indexing).
  4. Caching (Redis, CDN).
  5. Fault Tolerance (retries, circuit breakers).

Example: Design TikTok’s ‘For You’ Feed

  • Data Flow:
  graph LR  
      A[User Watch History] --> B[Recommendation Model]  
      B --> C[Cache (Redis)]  
      C --> D[API Server]  
      D --> E[Client]  
Enter fullscreen mode Exit fullscreen mode
  • Key Decisions:
    • Precompute feeds (reduce latency).
    • A/B testing for algorithm tuning.

Resources:

  • "Grokking the System Design Interview" (Educative)
  • TikTok Engineering Blog (Link)

✅ Days 12-14: Behavioral & Mock Interviews

Focus:

  • TikTok’s Core Values:
    1. "Rapid Iteration" (e.g., "Tell me about a time you shipped code quickly").
    2. "Data-Driven Decisions" (e.g., "How did metrics guide your project?").

STAR-LP Framework:

Situation: Video uploads were failing for 5% of users.  
Task: Debug and fix within 24 hours.  
Action: Traced logs, found AWS throttling, implemented retries.  
Result: Reduced failures to 0.1%.  
Lesson: Always monitor third-party API limits.  
Enter fullscreen mode Exit fullscreen mode

Mock Interviews:

  • Pramp (free peer practice)
  • Ex-TikTok interviewers (paid coaching)

3. Key Lessons Learned

  1. Prioritize Graph & DP Problems (60% of TikTok’s coding questions).
  2. Explain Trade-offs Clearly (e.g., "This is O(n) time but O(n) space").
  3. Align with TikTok’s Culture (mention "data-driven" and "fast iteration").

Top comments (0)