How do you improve your algorithmic thinking?
Arpit Nuwal

 

How to Improve Your Algorithmic Thinking

Algorithmic thinking is crucial for solving complex coding problems efficiently. Whether you're preparing for coding interviews, competitive programming, or just sharpening your problem-solving skills, here’s a structured approach to improving your algorithmic thinking.


1️⃣ Master the Fundamentals of Data Structures & Algorithms πŸ“š

Before tackling problems, ensure you understand these key concepts:
βœ” Data Structures: Arrays, Linked Lists, Stacks, Queues, Trees, Graphs, Hash Tables
βœ” Algorithms: Sorting (Merge Sort, Quick Sort), Searching (Binary Search), Recursion, Dynamic Programming (DP), Greedy Algorithms

πŸ’‘ Example: Knowing hash tables helps solve problems involving fast lookups (e.g., finding duplicates in an array).


2️⃣ Practice Pattern Recognition πŸ”

βœ” Recognize common problem types:

  • Sliding Window → Optimal for subarray problems
  • Two Pointers → Great for sorted arrays & linked lists
  • Backtracking → Used in permutations & combinations
  • Dynamic Programming (DP) → When problems involve overlapping subproblems
    βœ” Solve problems by category – Don't just solve problems randomly; instead, focus on one pattern at a time.

πŸ’‘ Example: Leetcode 121 (Best Time to Buy and Sell Stock) → A classic Kadane’s Algorithm problem.


3️⃣ Develop a Structured Problem-Solving Approach 🧠

1️⃣ Understand the Problem – Read carefully, identify input/output constraints.
2️⃣ Break it Down – Decompose it into smaller subproblems.
3️⃣ Think of Brute Force First – Find the simplest approach before optimizing.
4️⃣ Identify an Optimal Strategy – Use pattern recognition & known algorithms.
5️⃣ Implement & Optimize – Code the solution, analyze complexity, and refine.

πŸ’‘ Example: For Graph Traversal problems:

  • Brute Force → DFS (Depth-First Search)
  • Optimized → BFS (Breadth-First Search) for shortest path

4️⃣ Solve a Variety of Problems Regularly πŸ‹οΈ‍♂️

βœ” Use structured platforms:

  • Beginner: LeetCode (Easy), CodeSignal, HackerRank
  • Intermediate: LeetCode (Medium), Codeforces
  • Advanced: AtCoder, Codeforces (Div 2 & 1), Google Kickstart
    βœ” Aim for at least 1-2 problems per day to build consistency.

πŸ’‘ Suggested Leetcode List:
πŸ”Ή Easy: Two Sum, Valid Parentheses, Merge Two Sorted Lists
πŸ”Ή Medium: Longest Substring Without Repeating Characters, 3Sum, Binary Tree Zigzag Level Order Traversal
πŸ”Ή Hard: Edit Distance, Maximum Flow, N-Queens


5️⃣ Learn to Optimize with Time & Space Complexity ⏳

βœ” Always analyze Big-O complexity after solving a problem.
βœ” Try to reduce nested loops, use hash tables for O(1) lookups, and optimize recursive solutions with memoization.
βœ” Compare different approaches (e.g., DP vs. Greedy).

πŸ’‘ Example:

  • Brute force approach → O(N²) (nested loops)
  • Optimized approach → O(N log N) (sorting + two pointers)

6️⃣ Read & Analyze Other People’s Solutions πŸ“–

βœ” Study top-rated solutions on platforms like LeetCode Discuss, GeeksForGeeks, and Codeforces Editorials.
βœ” Understand different coding styles and optimizations used by top programmers.

πŸ’‘ Example: You might solve a problem in O(N²), but a top solution may use O(N log N) with sorting + binary search.


7️⃣ Compete & Challenge Yourself πŸš€

βœ” Join coding competitions:

  • Beginner: Google Kickstart, Codeforces (Div 3), Leetcode Contests
  • Intermediate: Codeforces (Div 2), AtCoder
  • Advanced: ICPC, Google Code Jam, TopCoder
    βœ” Competing improves problem-solving under pressure and exposes you to unique problems.

πŸ’‘ Example: Competitive programmers like Gennady Korotkevich (tourist) are exceptional due to regular contests & problem-solving practice.


πŸ’‘ TL;DR – Algorithmic Thinking Roadmap

βœ… Master Data Structures & Algorithms – Understand key concepts.
βœ… Recognize Problem-Solving Patterns – Sliding Window, DP, Two Pointers.
βœ… Follow a Structured Approach – Read, break down, optimize.
βœ… Practice Consistently – Solve 1-2 problems daily on LeetCode or Codeforces.
βœ… Analyze Time Complexity – Optimize solutions for efficiency.
βœ… Study Others’ Code – Learn from top solutions & coding editorials.
βœ… Join Coding Contests – Compete to improve speed and problem-solving.