### TheHoodyGang's blog

By TheHoodyGang, history, 7 weeks ago,

Since I want to progress, I wanted to know what all algorithms should I learn and what should I do to increase my rating.

• -6

 » 7 weeks ago, # |   +10 Learn basic STL. Then solve a lot of problems and upsolve them. This is the best way to improve.As one LGM said, if you're not red — go learn binary search
•  » » 7 weeks ago, # ^ |   0 Please explain why to learn binary search? I didn't get what you said
•  » » » 7 weeks ago, # ^ |   0 what I think he means is that jumping onto topics is less important and getting hold of what you're doing is more.
•  » » » 7 weeks ago, # ^ |   0 he also said that segment trees are important for beginners
•  » » 7 weeks ago, # ^ |   0 I have done binary search and STL. So I only need to practice?
•  » » 7 weeks ago, # ^ |   0 What does upsolving means?
•  » » » 7 weeks ago, # ^ |   0 Solve those problems after the contest which you were unable to solve during the contest.
•  » » » » 7 weeks ago, # ^ |   0 Thank you.
 » 7 weeks ago, # |   0 ur not cyan lol
•  » » 7 weeks ago, # ^ |   0 He wrote this blog from second account for privacy, I guess
•  » » » 7 weeks ago, # ^ |   +1 What algorithms should I practice as a grandmaster? (Im also writing on an alt for privacy)
•  » » » » 7 weeks ago, # ^ |   0 Practice binary search
•  » » » 7 weeks ago, # ^ |   +3 To prevent negative contribution hehe
 » 7 weeks ago, # |   +1
•  » » 7 weeks ago, # ^ |   0 Thanks a lot!
 » 7 weeks ago, # | ← Rev. 2 →   +3 Euler phi, sieve variants, trie tree, disjoint set union, binary exponentiation, modulo inverse/ Fermet's little theorem, topological sorting, dijkstra, floyd warshal, bellman ford, hashing, DP (coin dp, knapsack, LCS etc), segment trees, BITs etc. I also learnt some other DS and algos as part of my course syllabus like CRT, Edmond carp which I haven't found much use of. Also some other algorithms and techniques I learnt for fun like Sqrt decomposition, Mo's algorithm, Heavy light decomposition, Centroid decomposition have almost no uses below 2000 rating. I also learnt KMP, LCA, binary lifting. Problems related to these topics are fairly common in 1900-2000s. KMP is even found in 1700-1800s sometimes. It's a retarded thing to say that you don't need to learn algorithms. Not knowing the necessary algos can badly hinder your practice sessions especially if you are like me who hates looking at editorials
•  » » 7 weeks ago, # ^ | ← Rev. 2 →   0 Lol, you're funny. You don't need to know all these. Stop deceiving yourself. You're going to remain cyan for a long time.
•  » » » 7 weeks ago, # ^ |   0 I am expert in my alt id, your point?
•  » » » » 7 weeks ago, # ^ |   0 Lol, please. You were literally struggling to solve 4 problems in the last div3 contest. What is your alt so we see?
•  » » » » » 7 weeks ago, # ^ |   0 Alt id is alt for a reason. I wasn't struggling to solve 4 problems. I started half an hour late, and was sick so pretty much forcefully finished it. And I don't feel entitled to prove you a point, take it as you please
•  » » » » » » 7 weeks ago, # ^ |   0 The highest number of problems you've solved on this account in a div2 contest is 3, and you expect me to believe you're expert somewhere? Lol I am also LGM on my alt. Rofl. Dumbass.
•  » » » » » » » 7 weeks ago, # ^ |   0 Then don't. I fail to see why you are getting triggered
•  » » » » » » » » 7 weeks ago, # ^ |   0 This was your comment a few weeks ago, unsure of reaching expert and now you're expert? That's not even my business, what annoys me is the stupid list of topics you listed, even some reds don't know all those, and you think they are necessary as a cyan?
•  » » » » » » » » » 7 weeks ago, # ^ |   0 Yes, now I am. And you dug pretty deep into my blog history given that it's "none of you business". What is it that reds don't know? Point it out. In fact, you could do it in the very beginning. But instead, you kept badgering about how I will remain cyan for a long time
•  » » » » » » » » » 7 weeks ago, # ^ |   0 Yes, some of these topics are not necessary for cyans, you got the point, but I don't know why you assume that he doesn't know these topics. Studying Computer Science sometimes force people to learn algorithms and data structures, but simply knowing them doesn't mean you can successfully recognize them in problems and use them, and most of the time, you don't need to know any advanced topic to solve codeforces problem. And I think that reds in general know much more than algorithms listed here. Get some chill bro
•  » » » » » » 7 weeks ago, # ^ | ← Rev. 3 →   +3 I'm struggling with expert but I solve a whole Div.3 in average of 2 hours, so "I started half an hour late" should not be a reason. Spoileralso there's no reason to use an alt to post blogs
•  » » » » » » » 7 weeks ago, # ^ |   0 You are not struggling with expert. And you don't need to consistently solve whole div 3 to be above 1600. Regardless, I said it as it is. I only brought this up because somebody started nagging about how I will "remain cyan for a long time". It irritates me that I have to explain how I know what I am saying in a comment which has little to do with rating
 » 7 weeks ago, # | ← Rev. 2 →   +20 In my opinion expert is attainable with some speed and being comfortable with applying these algorithms:DFSBFSDSUBinary SearchMemo DPSieveBinary Exponentiation / Inv ModPrime Factorization