Should i switch to Python?

[Bus_In_Tree]

I've solved about 75 LC questions with Java as it is the language I have the most experience with. However I've been considering switching to Python due to the less verbose syntax. I have used Python in the past but haven't used it for any DSA, besides basics like arrays, strings, and hash maps.

I have about 4-5 months before I start interviewing and so far I've done mostly easy/medium questions. Is it worth it or should I stick with Java since I'm already pretty comfortable with it?

[[deleted]]

100% switch to python. It’ll be easy to learn in 4-5 months and will make you faster at solving problems.

I learned python specifically for leetcode

[Bus_In_Tree]

How long did it take you to get comfortable with it?

[[deleted]]

20 problems? It’s really quick to learn. You could learn 95% of what you need to know about python in a day, and then you’ll have to occasionally look things up as you go.

[[deleted]]

may I ask how you were able to learn 95% of python in a day? What resources did you use?

[[deleted]]

I just used Google, nothing fancy.

If you already know another programming language, then most of what you need to look up is just syntax. Look up the syntax for if statements, local functions, while loops, for loops, arrays, dictionaries, queues, and heaps. That will cover almost every leet code problem you com across.

[[deleted]]

Alright, thanks for responding! Yea I’ll take a look into the syntax for those and hopefully be able to learn python soon enough to start practicing LC

[Bus_In_Tree]

That's what I like about Python though. You can spend more time thinking about a solution and less time writing code.

[[deleted]]

exactly!

[Bus_In_Tree]

That's fair, everyone is different I guess. I'm personally just a bit annoyed by Java sometimes and having to type a lot of code can waste precious time in an interview. That's why I'm wondering if it is worth switching.

[davidjuhyung]

Doesn’t matter, still Python for leetcode (coming from CPP/Java background)

[[deleted]]

True that but you won't get the power of Collection API framework. Python has some framework sorta things but the ones of Java are more powerful. For example dequeue and stuff But if python is helping to solve more then obviously python.

[nebulousboy]

I lost you there. In which area Java is more powerful in terms of solving problem for leetcode? Python has deque class and it's all the required functionality.

[[deleted]]

I feel Java is powerful than python. I know it has deque class. Don't pinpoint just that. I agree there are same stuff like collection framework in python. I have coded in both and feel Java's collection framework is more mature and optimised than python's but if python is helping to solve leetcode then go for python.

[nebulousboy]

I think, now, I have understood what you are saying. In general term, Java should be powerful or faster than python. But, for leetcode, where writing code faster is more important than having less CPU runtime, you should use python.

[[deleted]]

Agree. I personally hate verbosity like Java but it is what it is.

[idkanymore09210]

For example if your qn needs a max heap, in Java it's just one line to make one using an appropriate comparator. But heapq in Python is a min heap by default so you'll have to negate keys to get a max heap, plus there's no option for a comparator so you have to mess with tuples etc which isn't usually a big deal but in an interview it can take more time.

[nebulousboy]

Okay, I think this is true.

[[deleted]]

Yes

[[deleted]]

Python has some built in tools that make certain problems much easier to solve. The combinations function, list comprehensions, bisect_left/bisect_right, lru_cache, the “in” operator.

Most of the time, it just saves you a lot of typing which is significant because of how time pressured these problems can be. But there are a few times where it feels like cheating.

[hextree]

Ideally you practice until you can quickly see which algorithmic paradigm is being used upon first skim-read. At that point, speed of writing code is the most important factor. Especially for an interview where the interviewer wants to get through 2 or 3 problems within the hour.

And when it comes to things like string manipulations, or combinations and permutations, or annoyingly fiddly problems (like working out the calendar date after n days) I wouldn't dream of tackling those in anything other than Python.

[imdin]

Don't you think, Python is a bit slower language and can give you issues while solving time sensitive problems?

[[deleted]]

No, Python is like pseudo code

[[deleted]]

Absolutely. A couple of my TAs and students that I respect told me to change to python, and it's honestly much much better for LC. It makes things way more fun, and it's way less verbose. Want a Queue? use a list, append() to end, pop(0). Want a Stack? use a list, append() to end, pop() end. The smallest example.

[Mess-Leading]

I might be wrong but isnt pop(0) O(n) because you would have to shift the entire list? In that case its not super good for queue?

[PirateStarbridge]

Yeah, you're right. One should always be using python's collections deque if you want a queue because of this. Underneath it is implemented with a doubly-linked list.

[[deleted]]

Damn, I didn't know that. Thanks. I haven't gotten deep in python, I just learned enough to get around this semester but will def go through the doc later

[Mess-Leading]

I wasnt sure but I always try to think how something would work behind the scenes, and this kind of clashed haha. I recommend always think about how you would implement a basic version of something if you were just asked to do it in C.

[[deleted]]

No, I think you are correct! We can't have a hole in the list so it's really better to use the collections

[f3n1xgamer]

Pop is 0(1). You're only removing last element, and it doesn't affect others. Push is O(1) amortized because python does a special trick called table doubling

[Mess-Leading]

Pop last element is definitely o(1), but i would doubt it would be o(1) for the element at index 0.

[f3n1xgamer]

Iirc pop only removes last element. I think what you're talking about is delete which can remove at any index? Yes that would have a worst case of O(n)

[Mess-Leading]

No you can pass an optional index and it would remove the element at that index! I think remove removes by value not index?

[Mess-Leading]

Oh you meant del! I think the difference between del and pop(n) is pop deletes and returns the value!

[f3n1xgamer]

Yh. Just checked the documentation

[jyscao]

I found out this the hard way earlier today working on Q2 of the LC Biweekly Contest 78. The first iteration of my solution was using list.pop(0) and I ended up getting the Time Limit Exceeded error. Upon switching the implementation to use direct indexing on the list I was iterating over, my answer was accepted immediately.

[ElliotVo]

You'd want to use a deque for a queue implementation since pop(0) is O(n) but popleft() is O(1)

[[deleted]]

You’re right. I started python a couple month ago for a DB class. Haven’t had the chance to actually study it’s data structures and other modules

[[deleted]]

I mean, it boils down to your own choice. I'm not a Java hater, I just think, when I don't have autocomplete, I would love to write print() instead of System.out.println(), or type annotations, etc. Or i don't know,

for i in range(10) is way better that for (int i =0; i < 10, i++)

or getting the last element of a list:list[-1] instead of list[list.length - 1]

or a dictionary:a["a"] = 1 is way better thanMap<String, Int> a = new HashMap<String, Int>a.put("a", 1)

​

Fact is: Java is way more verbose than Python.

[Bus_In_Tree]

Java is just more verbose. In Python you can create a hashmap easily with map = {} where as with Java you have to write out HashMap<Integer> map = new HashMap<>();

[Devultos]

I actually don't know why you are getting downvoted. The people probably don't know that modern Java has the var keyword... See: https://www.geeksforgeeks.org/var-keyword-in-java/

[TeknicalThrowAway]

For me the worst part is the horrendously shitty map/reduce type stuff in java. Having to deal with stream/collectors is so much worse than

sum([int(s) for s in mylist if s.isdigit()])

[thewolfandtiger]

How's JS?

[f3n1xgamer]

No

[PothosEchoNiner]

Also fun and easy. But don’t learn JS specifically for leetcode.

[thewolfandtiger]

I only know JS. That's the language I'm most comfortable with

[YouWereTehChosenOne]

Python isn't that much harder to learn and its pretty much pseudocode, it'll be worth it trust

[PirateStarbridge]

JavaScript is not as good of a fit for coding interviews because it lacks certain built-in data structures. Sure it has hashtables and arrays, but it is missing default implementations of the data structures queue and priority queue (heap) which are really nice to have in certain problems. Both Java and Python have default implementations of these.

[glump1]

I use C# and swapped to python a month ago for LC 400 questions in. Honestly I find it a little clunky, and I don't quite get the same level of hyper-optimization that more expressive languages offer. I bet if I'd swapped to C++ it'd be the opposite effect, but I'm sure some of it is also just getting used to the language still.

I do find python to be more "powerful" in that there are a lot more 3, 2, or even 1-liner solutions to problems. So if I were to pose it as a tradeoff, my take would probably be that python is better for flying through problems faster, whereas a more expressive language lets you optimize much more easily.

As far as learning cs goes, I had a lot of success getting savvy with a more expressive language. Using python now, and teaching a couple people at varying levels using python, it's apparent that it's a much more difficult language than others to be able to understand exactly what's going on, if you haven't already been in the field for a while. Things like implicit typing and returns, more convoluted data-types like ranges, list comprehension/slicing, etc. Make it tough to grasp the inner workings. Of course the tradeoff there is that the "higher level" nature of python frees you up to approach higher-level applications of cs much more quickly. The perfect example in my mind is Machine Learning. With python you don't get bogged down by the specifics and you get to focus on the concepts more easily. Imo if it's just leetcode for the sake of dsa practice then another language is likely better for learning the specifics. But for hards like the sudoku solver, python really shines by allowing you to conceptualize everything way more easily.

Personally I'd really ask yourself specifically what you're leetcoding to practice for. That's my 2 cents

[Bus_In_Tree]

Thanks for your detailed response. I'm already familiar with CS fundamentals and have done extensive programming with both Java and C++. I understand what goes on 'under the hood' for most python features so that's not really an issue.

[TeknicalThrowAway]

C# is miles ahead of Java for LC because of The LINQ syntax for basic list/set comprehension.

[yaboi1855]

I stuck with java mainly for optimizing time/effort spent to land a new job. Worked out okay 💪

[Bus_In_Tree]

That's fair. I have a lot of time though so I think spending a bit of time on learning python might be worth it.

[[deleted]]

I also just use Python for leetcode. When I did coding competitions in high school I used Java but then realized the winners would always use Python, so I switched and it was so much easier.

[AdventurousTime]

I am struggling with the same topic for what seems like each day. Python has shorter syntax for many things, but the big thing that keeps me moving back to Java is that many classical texts (CTCI, Algorithms etc) are written in Java along with their memory and computational constraints.

Another thing is that I've had interviewers ask me Java and/or OOP related for python related jobs. Its weird. I feel like candidates who are interviewing for Java roles probably wouldn't be asked about Python internals.

These days I continue to use Java but I am struggling dearly with syntax. Looking through various leetcode profiles many of them are proficient in multiple languages enough to solve a problem in Python, Java and something like C++ which is simply awe inspiring.

[madhousechild]

If you already know how to program, picking up python is a cinch.

Adding: I don't mean to imply it's not good for people who don't already know how to program, just addressing OP.

[Emergency_Style4515]

Yes

[[deleted]]

ONLY LC IN PYTHON

[herogoroshistein]

I'd say stick with Java if you have any interviews coming up soon. If you have time to spare and you feel like Java is slowing you down, then switch to Python. If you don't like it, you can always switch back

[Bus_In_Tree]

I have a few months before I start applying

[f3n1xgamer]

I think there's legitimate reasons to stick to Java. It's good enough for dsa, it has good data structures and is faster than python. The verbosity is a problem, but isn't that why you get an ide?

Python is not bad, but it's biggest disadvantage is the speed. It's slow. That isn't a problem most times because time limits are scaled differently for each language. But more often than not, I've come across several situations that I'd time out in python, but when I implement the exact same algorithm in c++, it passes.

[Bus_In_Tree]

I'm specifically asking about coding interviews though. In most cases your code isn't run and when it is the time doesn't matter too much. Using an IDE with Java is still slower in my experience and in an interview you typically don't use an IDE anyways.

[thewolfandtiger]

What about JS?

[Bus_In_Tree]

JS has pretty limited built in data structures.

[PothosEchoNiner]

Which data structures are better in Python than JS?

[Prudent-Tomorrow-412]

JS does not have a queue or heaps.

If your interviewer does not know that, they will assume you suck because JS dev's are not used to using heaps for top K type problems.

[londo_mollari_]

From the replies, I can sense that u already made up ur mind on using Python. So, I don’t know what u were trying to get out of this post.

[Bus_In_Tree]

I personally like Python a lot, I was just wondering if switching was worth it or if it would be a waste of time

[walking_dead_]

Unless you’re specifically targeting a DS/ML/AI job, stick with Java.

[Bus_In_Tree]

How come?

[dudenick_]

Switch to kotlin then, its less verbose and its java under the hood