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LeetCode dynamic programming
Home/Blog/Interview Prep/A beginner’s guide to LeetCode dynamic programming

A beginner’s guide to LeetCode dynamic programming

6 min read
May 08, 2025
content
Why dynamic programming is hard
Common DP patterns that show up on LeetCode
LeetCode problems to learn dynamic programming
Top mistakes beginners make in DP problems
Memoization vs tabulation: Which to use when
How to identify the state and recurrence relation
Visualizing DP tables to debug logic
When to optimize space in dynamic programming
How to stay consistent when learning DP
Resources beyond LeetCode for mastering DP
Practicing under interview conditions
Final thoughts

Dynamic programming (DP) is one of the most intimidating topics in coding interviews. It’s abstract, often unintuitive, and the problems on LeetCode can seem overwhelming, especially when you’re just starting out. But here’s the good news: with the right mental models and consistent practice, anyone can get good at dynamic programming.

In this blog, we’ll explain how to approach LeetCode dynamic programming problems, what DP patterns to focus on, and how to build the confidence to tackle even the toughest interview questions.

Grokking Dynamic Programming Interview

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Grokking Dynamic Programming Interview

Some of the toughest questions in technical interviews require dynamic programming solutions. Dynamic programming (DP) is an advanced optimization technique applied to recursive solutions. However, DP is not a one-size-fits-all technique, and it requires practice to develop the ability to identify the underlying DP patterns. With a strategic approach, coding interview prep for DP problems shouldn’t take more than a few weeks. This course starts with an introduction to DP and thoroughly discusses five DP patterns. You’ll learn to apply each pattern to several related problems, with a visual representation of the working of the pattern, and learn to appreciate the advantages of DP solutions over naive solutions. After completing this course, you will have the skills you need to unlock even the most challenging questions, grok the coding interview, and level up your career with confidence. This course is also available in C++, JavaScript, and Python—with more coming soon!

25hrs
Intermediate
44 Challenges
868 Illustrations

Why dynamic programming is hard#

Most learners struggle with dynamic programming because it demands more than just code memorization. It forces you to:

  • Break down problems into subproblems

  • Identify overlapping computations

  • Think recursively before optimizing

  • Track state transitions and base cases

Unlike simpler algorithm problems, DP often requires a shift in mindset. The challenge lies in abstract thinking and maintaining clarity across layers of recursion and optimization. To get better at LeetCode dynamic programming, start by mastering the underlying thought process, not the syntax. Try this step-by-step strategy:

  1. Start with recursion: Write the brute-force solution to understand the structure.

  2. Use memoization: Add caching to avoid redundant calls.

  3. Convert to tabulation: Rebuild the logic bottom-up for performance.

  4. Track state explicitly: Write down your variables and how they change.

Common DP patterns that show up on LeetCode#

The best way to simplify LeetCode dynamic programming problems is to group them into repeatable patterns. These patterns appear repeatedly across questions with slight variations. Here are the most common:

  • 0/1 Knapsack: Subset sums, decisions to include or exclude items

  • Fibonacci: Recurrence with base cases and cumulative answers

  • Longest common subsequence: Comparing sequences character by character

  • Partitioning: Splitting arrays or strings into segments

  • Palindrome: Using symmetry and caching results of inner substrings

Once you start to recognize these patterns, your problem-solving becomes much faster and more intuitive.

LeetCode problems to learn dynamic programming#

Here’s a curated list of LeetCode dynamic programming problems to practice as a beginner:

  • Fibonacci Number (Easy)

  • Climbing Stairs (Easy)

  • House Robber (Medium)

  • Coin Change (Medium)

  • Longest Palindromic Substring (Medium)

  • Longest Common Subsequence (Medium)

  • Word Break (Medium)

  • Decode Ways (Medium)

  • Edit Distance (Hard)

  • Burst Balloons (Hard)

These problems are chosen for their pedagogical value — they build on one another, teaching you transitions, state tracking, and space optimizations. Start with the easier ones and move up as your understanding improves. Redo problems after a few days to test your retention.

Top mistakes beginners make in DP problems#

Avoid these common pitfalls that often slow down progress:

  • Skipping the recursive brute-force step and jumping straight to optimization

  • Not writing down the state clearly before coding leads to confusion

  • Trying to memorize solutions without internalizing the problem structure

  • Misplacing the base case or misunderstanding overlapping subproblem logic

  • Failing to visualize how recursion unfolds over time

Being aware of these mistakes early on can dramatically improve your learning curve and save hours of frustration.

Memoization vs tabulation: Which to use when#

Here's a breakdown of what memoization vs. tabulation in dynamic programming entails.

Memoization is great when you want to extend your recursive logic with minimal changes. It’s intuitive, mirrors your thought process, and is easier to debug. Tabulation, however, tends to be more efficient and forces you to think about the order of subproblem evaluation.

Memoization is helpful for prototyping or exploring problem structure. Tabulation is essential when optimizing for time and space in interviews. Learn both and practice converting recursive solutions to bottom-up tabulation. This exercise strengthens your understanding of dependencies and state.

How to identify the state and recurrence relation#

Every DP problem hinges on two questions:

  1. What state(s) do I need to track to uniquely define subproblems?

  2. How can I express the current solution in terms of previous states?

Always break your problem into its smallest input changes — a pointer index, a remaining sum, or a boolean flag. Write out the recurrence relation clearly, either in words or as a math formula. This gives structure to your implementation and helps you debug effectively.

Visualizing DP tables to debug logic#

When debugging, sketch out the DP table on paper or use print statements to see how values evolve. This is especially helpful in tabulation, where mistakes in iteration order can lead to wrong results.

A visual table helps you track transitions, spot bugs, and verify base cases. If needed, use colored pens or a spreadsheet. It’s a powerful tool for turning abstract code into something tangible.

When to optimize space in dynamic programming#

Not all DP problems require a full 2D table. Once you understand the dependency structure, many problems can be optimized to use just one or two arrays. This is called space optimization.

Common examples include Fibonacci, House Robber, and even Longest Common Subsequence with a rolling array. Start with the full table to get it working, then refactor for space once you're confident in the logic.

How to stay consistent when learning DP#

Learning DP is like building muscle — repetition and reflection matter more than speed. Create a personal log where you record:

  • The problem link

  • What pattern it belongs to

  • What you got stuck on

  • What you’d do differently next time

  • Whether it involved 1D or 2D state

  • What the base case and recurrence were

This journal becomes your personal playbook. Use it to review before interviews and to cement patterns into memory.

Resources beyond LeetCode for mastering DP#

While LeetCode dynamic programming problems are excellent, you can diversify your prep with other resources:

  • Educative’s “Grokking the Coding Interview” visual approach for guided pattern recognition

  • HackerRank and Codeforces for practice under timed pressure

  • FreeCodeCamp’s DP curriculum for fundamentals and visuals

  • YouTube walkthroughs by engineers breaking down DP with real-time reasoning

Mixing different formats helps you absorb concepts faster and reinforce them from multiple angles.

Practicing under interview conditions#

Solving dynamic programming problems in isolation is one thing — solving them in an interview setting is another. To prepare for the real thing:

  • Time yourself (e.g., 30–45 minutes per problem)

  • Practice writing clean, bug-free code in a single pass

  • Simulate thinking aloud to explain your approach

  • Start with brute-force and build toward optimal, narrating trade-offs

  • Focus on clarity, not cleverness — interviews reward structure over shortcuts

Practicing under time constraints with a clear process will prepare you to stay calm and structured when it counts.

Final thoughts#

Dynamic programming is less about being clever and more about being consistent. The more you expose yourself to patterns, the more they’ll start to feel familiar. If you’re struggling with LeetCode dynamic programming, remember that most developers do — until they don’t.

Take it slow, write things down, and don’t skip the brute-force step. With time and deliberate practice, you’ll build the muscle memory to crack dynamic programming problems in any interview.

Don’t chase shortcuts — build your own internal map. The more patterns you internalize, the faster you’ll recognize them. And the moment DP “clicks,” you’ll never look at interview prep the same way again.


Written By:
Areeba Haider

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