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Coding Interview Roadmap

February 5, 2026 💻 Programming & Development
interview dsa roadmap leetcode

Coding Interview Roadmap

Structured 100-day plan to prepare for software engineering technical interviews. Focus on consistency and pattern recognition.

Phase 1: Weapon of Choice (Days 1-20)

Goal: Master one programming language (Python, Java, or C++).

  • Syntax: Loops, conditionals, functions, classes.
  • Standard Library: Lists, Maps, Sets, String manipulation.
  • Complexity: Understand Big O (Time & Space).
  • Debugging: Learn to use debugger or print statements effectively.
  • Setup: Configure IDE (VS Code/IntelliJ) with snippets.

Phase 2: Mastering Basics (Days 21-60)

Goal: Learn core Data Structures & Algorithms.

Week Topic Problems
4-5 Arrays & Hashing Two Sum, Contains Duplicate, Valid Anagram
6-7 Two Pointers & Sliding Window Valid Palindrome, Max Subarray
8-9 Stack & Linked Lists Valid Parentheses, Reverse Linked List
10-11 Trees & BST Invert Tree, Level Order Traversal
12-13 Backtracking & Heaps Subsets, Top K Frequent Elements

Phase 3: Starting Practice (Days 61-80)

Goal: Apply knowledge to medium-difficulty problems.

  • Pattern Recognition: Identify if a problem is DP, Graph, or Greedy.
  • Blind 75: Start solving the curated Blind 75 list.
  • Time Limits: Aim to solve Easy in 15 mins, Medium in 30 mins.
  • Mock Interviews: Use Pramp or interview friends.

Phase 4: Getting Better (Days 81-100)

Goal: Refine skills and tackle hard problems.

  • Dynamic Programming: Climbing Stairs, Coin Change, LCS.
  • Graphs: Number of Islands, Clone Graph, Course Schedule.
  • System Design: Basic scalability concepts (Load Balancers, Caching).
  • Review: Re-solve previously failed problems.

Daily Routine

  1. Warm-up: 1 Easy problem (15 mins).
  2. Deep Work: 1 Medium problem (45 mins).
  3. Review: Analyze solution & optimal complexity (30 mins).
  4. Notes: Update personal cheat sheet with new patterns.

Resources

  • Practice: LeetCode, HackerRank, Codeforces.
  • Learning: NeetCode.io, GeeksForGeeks, Cracking the Coding Interview.
  • Tracking: Use a spreadsheet to track solved problems and revisit dates.

Rule: Don't memorize code. Memorize patterns. If stuck for >30 mins, look at the solution, understand it, then implement it yourself the next day.