How I Got Good at Coding Interviews

Hey guys, it's me again and today I want to talk a little about how I got good at my coding interviews when I was preparing for them and how you can prepare for yours as well. And I know a lot of people on this channel probably think that I'm a genius from the solutions videos, but I'm going to show you I'm not a genius and you really don't have to be a genius either. Now of course we all know that coding interviews today center a lot on algorithms, so I'm going to be talking somewhat about that. But there's also some clever stuff you can do to prepare, what I like to call cheat codes, and I'll touch upon that as well. First, let me give you a quick history lesson about a list of 75 leetcode questions. So there was a Facebook tech lead a couple years ago who compiled this 75 list of questions from a couple hundred or something that they were looking at and they found that these 75 questions were the most helpful, they were the most comprehensive, they covered the most amount of patterns that you needed to know for a coding interview. And this list has become very infamous in the software engineering community and on online forums. Like if you go on Reddit and you know you'll see this list mentioned a lot, like you'll see it mentioned in Reddit, you'll see it mentioned on Blind a lot, you'll see it mentioned when people ask about which problems should I study. And even this list of 170 questions that I posted in a previous video is actually based upon this Blind post. A lot of things have been created from this one post. If you go on leetcode, there's a dedicated list to these 75 questions, and over 12,000 people have viewed it. So you know that there's something good about these problems. So that sounds easy enough, right? 75 questions, that's it. These are really good problems, they have everything you need, just solve all of them, right? So of course, it's not that easy, right? Some of these problems are extremely difficult. WordSearch 2 is just one example. Try solving this problem on your first try in 30 minutes without having seen the solution before. Very few people can. I like to call this a crackhead problem, because if you can solve this problem in 30 minutes in an interview while explaining your solution, creating a bug-free solution without having seen this problem before, you must be doing some crack or something else to be doing that. There's just no way that you could do that. So that's the problem, right? There's only 75 questions, but some of them are extremely difficult. So then the next thing people do, they go to the discuss section, this person is really smart, they made a really good post about it, they tell you all these little details about it, right? Now you can take a look at this and try to learn from it, right? But some people are just going to go straight to the code and try to memorize every semicolon, every little detail about the problem. There's just no way you can do that. At least I wasn't able to, so I took a slightly different approach. I did solve these 75 questions. I did not try to memorize every line of code in every detail. This is the workaround that I found. Instead of memorizing code, how about I memorize the patterns, right? So to sum, you use a hash map, you keep track of an index, something like that, right? No code, this is English, right? And I didn't even write that much. I just wrote one or two sentences. For word search too, you can take a look at some of the notes that I wrote. I don't think it'll be helpful for you. It's probably not even helpful for me because I don't even remember what I wrote. So, and I'm sure you guys probably have similar experiences when you go back to review some of your notes, but that's like the idea, right? Don't memorize 30 lines of code where if you forget a single semicolon, you're screwed. Try memorizing one or two sentences, one or two patterns. For word search too, you can see that I said, oh, there's a little trick to this problem. There's a really clever trick that you can just memorize. And you can see that I did similar things as well as I mentioned in previous videos, right? Grouping similar problems together, array questions together, dynamic programming questions together. You'll notice that dynamic programming questions use a lot of the same patterns, a lot of the same algorithms. You know, go to tree questions. They're actually not as different as you think. Look at this, recursive depth-first search, recursive depth-first search, recursive depth-first search, right? That's what I mean by, hey, some of these problems are actually really similar to each other. Now, the last thing I'm going to show you, if all else fails, go to leak code, discuss section, and go to the interview section, the interview questions section. And supposedly, people share which interviews, like what interview questions they got at which company. Somebody posted what they got in a Walmart online assessment. Don't tell anybody I sent you here. And I can't really confirm how accurate these are because it is user-generated. And of course, some of it might be outdated. Like you can see, this is 2019, 2019. But it's at least a resource that I think a lot of people don't know about. At the very least, you might know that, hey, maybe this company focuses on certain data structures. Like if you go here, Microsoft online assessment, like this is the long list of questions. So it might not even be helpful for you because if there's 1,000 questions that they ask, knowing that list might not be helpful. But it's at the very least a resource that I think you might not have known about. So those are the main things that I want to talk about unless I'm forgetting something. But if this was helpful, please like and subscribe. Thanks for watching. Leave any feedback that you want. I might make more leak code solution videos. I might focus on other things. I'm not really sure right now. Who knows? And yeah, thanks for watching.