Grind 75 vs. LeetCode patterns: Best prep for DoorDash interviews

For most developers, the process starts the same: a quick search on how to prepare for a DoorDash coding interview. Before long, you’ve got Grind 75 open in one tab and LeetCode patterns in another, trying to figure out which path will help you land the job. The truth is, each takes you in a different direction.

DoorDash, a company built on rapid logistics and complex real-time systems, is known for fast-paced interviews that test fundamentals and adaptability. So, is grinding through 75 questions enough, or do you need the versatility that LeetCode patterns promise?

In this blog, I will compare Grind 75 and DoorDash top 75 against the 28 LeetCode patterns from Grokking the Coding Interview Patterns. We’ll see how each approach stacks up, measure how well they cover DoorDash’s favorite coding interview problems, and show you how to combine them into a roadmap that actually works.

Sneak peek: How we evaluated DoorDash interview prep strategies

Blind 75, Grind 75, NeetCode 150, or LeetCode patterns? Ask 10 engineers and you’ll get 10 different answers. These lists are popular for good reason, but popularity doesn’t always equal effectiveness. However, without a standard benchmark, knowing which approach prepares you for DoorDash’s interview style is impossible.

I wanted to move beyond opinions and measure each prep strategy against something objective. Therefore, I developed a rubric and scoring method, introduced in the first blog, Grind 75 vs. LeetCode Patterns: Most Effective for Interviews? of this series, to objectively evaluate coding interview prep strategies.

The rubric is simple. A pattern only counts as well-covered if it includes at least one easy, two medium, and one hard problem. An easy coding problem is worth 1 point, a medium coding problem is worth 4 points, and a hard coding problem is worth 6 points. Together, that’s 15 points per pattern. Multiply by 28 patterns, and you get a benchmark score of 420 points, representing the complete LeetCode pattern coverage.

With this rubric, we can see whether Grind 75 or DoorDash 75 covers a pattern and whether it prepares you enough to handle different levels of difficulty. Let’s now examine the effectiveness of Grind 75 and DoorDash’s top 75.

Looking at the chart, something stands out: the DoorDash-focused roadmap clearly outperforms both Grind 75 and DoorDash top 75. But what exactly is this roadmap, and why does it score higher than either list? That’s the question we’ll answer in the next sections.

Grind 75, DoorDash top 75, and LeetCode patterns: Quick overview#

Grind 75 is a curated list of 75 LeetCode problems designed to give candidates a focused way to practice the must-know interview questions. It’s popular because it covers core areas like arrays, linked lists, binary trees, and graphs. These problems strengthen the fundamentals every engineer needs.

DoorDash top 75 is not an official list from DoorDash. Rather, it’s a community-driven collection of the most frequently asked DoorDash questions on LeetCode. Think of it as a snapshot of coding patterns interviewers at DoorDash have frequently asked.

LeetCode patterns are the underlying frameworks that most coding interview questions follow. There are 28 well-known coding patterns, and a few examples include Sliding Window, Two Pointers, and Backtracking. Recognizing these patterns gives you the flexibility to tackle problems you’ve never seen before, instead of relying only on recall.

Is Grind 75 all you need for DoorDash coding interview prep?#

Grind 75 is a strong starting point, but stopping there leaves gaps if you’re targeting DoorDash. Here’s why:

1. It can give a false sense of security: Because Grind 75 is a fixed list, it’s easy to think finishing it means you’re done. In reality, DoorDash interviews often push problems to higher difficulty tiers. You may not be ready for those escalations without practicing patterns across easy, medium, and hard levels.

2. It can encourage memorization over mastery: Because Grind 75 is a fixed, finite list, many candidates end up memorizing solutions rather than developing the skill of recognizing and applying underlying patterns. This works if the interviewer asks the same problem, but falls apart the moment DoorDash introduces a variation, which they almost always do.

3. It was designed with FAANG in mind, not DoorDash: Grind 75 was created a few years ago, when curated lists mainly focused on FAANG-style interviews. Since then, the technical landscape and interviewer expectations have evolved drastically. DoorDash, being a newer player, emphasizes different problem styles that Grind 75 doesn’t fully capture. The gap is obvious: if you look at DoorDash’s top 10 most frequently asked LeetCode questions, none appear in Grind 75.

How LeetCode patterns give you an edge in DoorDash interview prep#

LeetCode patterns train you to see beyond the question in front of you. For DoorDash interviews, where speed and adaptability are crucial, that’s the edge you need.

1. Patterns prepare you for variations: DoorDash rarely asks textbook questions. They’ll take a familiar concept like shortest path and layer in delivery windows, route limits, or resource constraints. If you’ve memorized one solution, you might get stuck. If you understand the underlying pattern, you can adapt on the go.

2. They shift your mindset: Patterns change the way you think in an interview. Instead of asking: Have I seen this exact problem before? You ask: Which pattern does this belong to, and how do I apply it here? That shift is what separates strong candidates from those who freeze on unfamiliar questions.

3. They integrate well with DoorDash-specific prep: Patterns aren’t meant to replace company-focused lists. They act as building blocks behind most coding interview questions. Once you recognize the patterns, plugging in DoorDash top 75 questions becomes far more effective, because you can solve them faster and generalize the learnings to other unseen problems.

LeetCode patterns overview for DoorDash coding interviews#

With 28 coding patterns to cover, it’s easy to feel overwhelmed about where to start your interview prep. To simplify your prep, I’ve grouped these patterns into four categories based on how they typically appear in DoorDash’s coding questions.

• Must-know patterns: These are the patterns that show up most frequently in DoorDash interviews. Practicing them is non-negotiable if you want to feel confident under pressure.

• Very common patterns: These appear regularly enough that skipping them is not good. Practicing them ensures you can handle most variations with confidence.

• Solid but situational patterns: These come up less often, but when they do, recognizing them quickly can give you a strong edge. Being ready here often makes the difference between finishing strong and falling short.

• Finishing-line helpers: These are the least frequent, but they still matter. Covering them ensures you don’t walk into your interview with gaps.

DoorDash might focus on some patterns more than others, but the smartest strategy is still to cover all 28. That way, no matter which variation or constraint shows up, you’ll already have the right blueprint to solve it.

DoorDash coding interview roadmap#

Most candidates approach DoorDash prep by jumping between lists, hoping they’re covering the right ground. The truth is, lists and patterns aren’t competing strategies. They’re complementary. Use a list to know what to practice. Use patterns to guide how to reason. A structured roadmap blends the two, combining Grind 75, DoorDash’s top 75, and LeetCode patterns into a single, complete interview prep plan.

Here’s how to approach it step by step:

1. Start with the Grind 75-DoorDash 75 overlap: Begin your DoorDash coding interview prep with the problems that appear in both Grind 75 and DoorDash’s top 75. These are proven questions that are widely practiced and directly relevant to DoorDash, giving you a strong base.

2. Move to DoorDash-only questions: Once the overlap is complete, shift to the problems unique to DoorDash’s top 75. These capture DoorDash’s distinct interview style and introduce variations you won’t see in a general-purpose list like Grind 75.

3. Work through the remaining Grind 75 problems: After finishing the DoorDash-specific sets, return to the rest of Grind 75. These questions strengthen your grasp of core data structures and algorithms, ensuring you don’t miss fundamentals that can still show up in interviews.

4. Fill the gaps with pattern-focused practice: Finally, check your progress against the 28 LeetCode patterns. Any pattern that isn’t fully covered becomes your priority for targeted practice. This step guarantees you aren’t just solving problems, but mastering the underlying techniques that make you adaptable in the interview room.

As you work through this DoorDash-focused roadmap, keep checking your progress against the 1–2–1 rubric. It’s the simplest way to stay on track and make sure every practice session brings you closer to full coverage of all 28 patterns.

Why start your prep with Grind 75-DoorDash 75 overlap?#

Starting with the overlap gives you two advantages right away. First, you practice problems that are both widely recognized and directly relevant to DoorDash interviews. Second, it builds confidence early in your prep because every problem you solve strengthens fundamentals while also targeting what DoorDash interviewers actually ask. It is the most efficient entry point into your roadmap.

Let’s place both, Grind 75 and DoorDash's top 75 coding problems, next to each other to identify the coding problems that appear in both lists.

The comparison above shows that there are 10 problems common to both Grind 75 and DoorDash top 75. Considering DoorDash was never the target of Grind 75, this overlap is a good number to start with.

Now, let’s see what patterns are covered by this overlapping set and to what extent they are covered as per the 1–2–1 rubric. In the bar chart below, each bar represents a pattern. The length of the bar shows what percent of the full 15 points you’ve earned for that pattern, while the label highlights how many easy, medium, and hard problems went into that score.

Note: For this calculation, I have only considered the counts that satisfy our 1–2–1 rubric. If a pattern has more questions than required by the rubric, I count only 1 easy, 2 medium, and 1 hard problem. For example, if Dynamic Programming has 10 medium questions, I have included just 2 in this calculation.

The overlap of Grind 75 and DoorDash top 75 introduces 7 out of 28 patterns, including some important ones. Dynamic Programming stands out with partial coverage. Others, like Stacks, Tree Depth-First Search, and Trie, are introduced but remain underrepresented, meaning you’ll need more practice later to reach full depth. Even though coverage is light for now, this early exposure is valuable because you can now apply the 1–2–1 rubric to build them toward full coverage.

Why practice DoorDash-only coding questions next?#

Once you’ve built a base with the overlap, the next logical step is to focus on the DoorDash-only questions. These problems capture the company’s distinct interview style and often come with twists you won’t see in a general-purpose list like Grind 75. Practicing them ensures you’re not just solid on fundamentals but also ready for the variations DoorDash interviewers are known to test. This step makes your prep more targeted and directly relevant to the role you’re aiming for.

Let’s see which LeetCode patterns are covered by the DoorDash-only questions.

The list above shows that the DoorDash-only coding problems introduce 15 new patterns, bringing the total to 22 out of 28. That’s about 79% coverage, which is a huge milestone. It also shows that the DoorDash prep roadmap is moving in the right direction.

Now, let’s see how well the patterns in this set are covered as per the 1–2–1 rubric. The bar chart below highlights the newly covered patterns in green on the y-axis.

The DoorDash-only set takes the roadmap to the next level. Several patterns that were introduced in the overlap, like Dynamic Programming, Stacks, Tree Depth-First Search, Trie, and Union Find, now move into the well-covered zone. That’s a big step forward in both depth and confidence.

We also see many other key patterns enter the picture with partial coverage, such as Sliding Window, Merge Intervals, and Backtracking. A few patterns remain underrepresented, including Modified Binary Search, Greedy Techniques, and Hash Maps. These patterns will need targeted practice later to close the gaps.

What is the impact of completing Grind 75?#

Finishing Grind 75 rounds out your fundamentals. Even though it wasn’t designed for DoorDash specifically, completing the list ensures you have strong coverage of core data structures and algorithms that can show up in any interview. It also strengthens several patterns that were only partially covered in earlier stages, moving them closer to full coverage.

Most importantly, it fills in the gaps left by DoorDash-only questions. By practicing the remaining Grind 75 problems, you’re building the versatility to handle unexpected coding questions in the interview room.

Let’s see which patterns the Grind 75-only coding problems cover.

The list above shows that the remaining Grind 75 coding problems introduce 4 new patterns, taking the total to 26 out of 28 (about 93%). This is a good jump in coverage.

Now, let’s see how well these patterns are covered as per the 1-2-1 rubric.

Completing Grind 75 gives the roadmap a big boost. Several previously identified patterns that were only partially covered before, like Two Pointers, Backtracking, and Stacks, now move into the well-covered zone. Dynamic Programming, Tree Depth-First Search, and Graphs also strengthen further, leaving you with a strong foundation across many core categories.

That said, a handful of patterns remain underrepresented, such as Fast and Slow Pointers, In-Place Linked List Manipulation, and K-Way Merge. These will need targeted practice if you want to reach complete coverage.

Is your DoorDash coding interview prep done?#

At this stage, you’ve worked through the overlap, the DoorDash-only problems, and the rest of Grind 75. The question now is simple: have well have you covered all 28 patterns? The bar chart below gives a clear snapshot of where your DoorDash prep stands overall.

Looking at the overall picture, 13 out of 28 patterns have now reached the green zone, meaning they’re well covered. This is a strong milestone, nearly half of the patterns are at full depth across easy, medium, and hard.

Another 6 patterns are in the yellow zone with partial coverage. For these, you’re only a couple of problems away from turning them green. Practicing one easy and one hard problem for each will be enough to close the gap.

The remaining 9 patterns are still underrepresented in red. Most of these need 2–3 additional problems across difficulty levels to bring them up to full coverage.

The good news is that two of the patterns, Cyclic Sort and Bitwise Manipulation, were previously not covered at all, and this roadmap finally exposed them. That means you can now apply the 1–2–1 rubric to bring them into alignment with the rest. Here are some recommended coding problems to practice for Cyclic Sort and Bitwise Manipulation.

Patterns recap for DoorDash coding interview prep #

Pattern coverage doesn’t just show you what you’ve solved, it reveals how balanced your prep really is. By breaking down the roadmap stage by stage, we can see exactly which sets contributed the most to covering the 28 patterns.

The coverage breakdown shows that more than half of the patterns came from the DoorDash-only questions, making this stage the single biggest contributor to overall progress. The overlap set also played an important role by covering a quarter of the patterns early, while the Grind 75-only problems added another slice of coverage to push the total further. By the end, only a small fraction of patterns remained uncovered, which have now been identified.

Score summary for DoorDash coding interview prep#

Coverage is one thing, but how does it translate into real progress toward the 420-point benchmark? The score breakdown below tells the story.

The score breakdown shows a total of 279 points out of 420, which is about two-thirds of full coverage. The biggest contributor by far is the DoorDash-only set, adding 187 points on its own. This is where most of the depth and company-specific focus comes in.

The Grind 75-only problems add another 53 points, strengthening fundamentals and filling gaps left by the DoorDash list. The common overlap contributes 39 points. It's a smaller number, but a valuable starting base that ensured early exposure to key patterns.

With 141 points still remaining, the roadmap has taken you a long way, but also clearly highlights what’s left to reach complete coverage. We can do that easily with 1-2-1 rubric in hand.

Final take: Grind 75 or LeetCode patterns?#

Grind 75 gives you a strong foundation, and DoorDash’s top 75 adds company-specific focus. But neither provides the adaptability that LeetCode patterns offer. Patterns are what enable you to handle unexpected variations. When combined with these lists in a structured roadmap, they ensure complete coverage of all 28 patterns and prepare you for the kinds of challenges DoorDash interviewers are known for.

The most important takeaway is about building the skill to recognize and apply patterns under pressure. That’s what will make you stand out in the crowd.

So if you’re serious about DoorDash, don’t just grind problems. Build a prep plan that balances breadth, depth, and adaptability. Start with the overlap, move into DoorDash-only questions, strengthen with the rest of Grind 75, and close the gaps with pattern-focused practice. That’s how you walk into your interview fully prepared and confident.

Recommended resources to level up your coding interview prep#

While this blog offers you a data-driven way to measure and close your prep gaps, the right learning tools can accelerate your progress even further. Here are two highly effective resources to complement your study plan:

• Educative’s Personalized Interview Prep: It’s your tailored prep companion that adapts to your skill level and focuses on the 28 essential LeetCode patterns we’ve been discussing. You can work on the patterns that need the most attention, track progress with clear metrics, and know exactly what to tackle next. Whether it’s adding an easy problem to build confidence or a hard one to push for mastery, you’ll always be working on the right problems at the right time.

• Educative’s Mock Interviews: Practicing is not just about solving problems. It is also about handling real interview pressure. Educative’s AI mock interviews let you simulate actual interview conditions, get actionable feedback, and improve in areas like problem-solving speed. This way, you are not only technically prepared, but also confident and ready to perform under time constraints.