Preparing for an SDE interview, especially when it comes to algorithms, can be tough. The more advanced problems often seem overwhelming, and there are so many techniques to learn. But I quickly realized that the key to succeeding wasn’t just doing more problems—it was about doing the right ones. Here’s how I got through the harder algorithm questions.
At first, I noticed that big tech companies often focus on a few key types of problems, like dynamic programming, graph algorithms, greedy algorithms, and backtracking. These types of problems come up a lot in interviews. So, instead of solving random problems, I started focusing on the most commonly tested ones. For example, Google tends to focus more on dynamic programming and graph problems, while Amazon leans towards greedy algorithms and working with arrays.
When I worked on dynamic programming problems, like "Longest Increasing Subsequence," I realized that the trick was understanding how smaller problems connect. Once I figured that out, it helped me solve similar problems, like "Longest Common Subsequence" (LCS).
This method worked well for LCS too.
Over time, I realized that just doing more problems didn’t make me better. What helped most was understanding how each algorithm works. I started organizing algorithms based on the types of problems they solve. For example, dynamic programming is great for problems that need the best solution, like the knapsack problem. BFS is good for finding shortest paths, and DFS is useful for checking if things are connected.
In the "Word Ladder" problem, I knew I needed to use BFS to find the solution step by step.
I also started practicing mock interviews. It’s not just about solving the problem—it’s about clearly explaining your thought process. I did mock interviews with friends who were also preparing. We worked through the problem in English, from understanding it to coding and analyzing time complexity. This really helped me get ready for the real thing. I remember struggling with the "Median of Two Sorted Arrays" problem at first, but once I used a divide-and-conquer approach, I was able to solve it.
Looking back, those advanced algorithms weren’t so hard. The key is focusing on the right problems, reviewing what you’ve learned, and practicing how to explain your solutions. If you’re preparing for an SDE interview, these tips should help. Stick with it, and eventually, you’ll feel more confident.
Release time:2025-04-17
