5th in Codeforces Round 744 - Facecam + Commentary + Solutions
Вставка
- Опубліковано 22 тра 2024
- Contest link: codeforces.com/contest/1579
My submissions: codeforces.com/submissions/ga...
Awesome... making a thunderous return to Div. 3's.
Timestamps:
Intro 00:00
A (solving) 00:23
B (solving) 01:37
E1 (solving) 07:03
D (solving) 10:55
C (solving) 15:08
E2 (solving) 25:29
F (solving) 30:48
G (solving) 38:14
Contest review + 4th 50:37
A (solution + code) 56:37
B (solution + code) 1:00:10
C (solution + code) 1:05:21
Dropping to 5th 1:13:28
D (solution) 1:14:21
E1 (solution + code) 1:17:40
D (code) 1:20:25
E2 (solution + code) 1:21:03
F (solution + code) 1:28:52
G (solution + code) 1:42:02
Outro 1:52:23 - Наука та технологія
![A Deep Understanding of Dynamic Programming [Intro / Overview]](http://i.ytimg.com/vi/Clp5c7HvLqs/mqdefault.jpg)
What a legend! Competed in the contest, came 5th, explained every problem, solution and the code, with 22 minutes sill remaining. hats off
Congratulations for your amazing performance today!
I was so glad to see that my technique for E2 was almost same like yours. I read about the less_equal trick in an ordered set on a cf blog, and got lucky.
hey buddy can you give me a link for this
the man, the myth, the legend
You are so good. I mean you performed way better than those who are using double monitors by using a 13 inch macbook.
Like?
Got my best performance so far! Super elated
love these explanations
Awesome explanation for problem G.
Great video, loved it
Hey Colin. Love your vods. Just up solved G(thanks to you).
For problem G, I was thinking the maximum possible width will be 2000.
Coz in the worst case, at any moment, we will be in the exact middle of the width(or else we can move to either of the larger halves).
I am not sure. Maybe I'm wrong.
Yes, the maximum possible answer is 2000, for the exact reason you mentioned. Now I'm interested... did you submit a guess, or somehow solve G without that fact?
Yes, it was a guess. Worked out 😅.
Awesome! sir.
I completely forgot about the fact that D was greedy. Used up a lot of time through 2 pointers. Could've solved it a lot earlier by using priority_queue
dude you're good
daily colin
Awesome colin. I solved 5/8 this time.
did u reach specialist?
@@noobygenius6023 You can watch first 2 problem solutions on my channel by the way. Going to post more such solutions of CF and leetcode.
How did you create that compr command ? and also what's your typing speed and thinking speed ?
Amazing
Colin is there a reason you do i++ instead of ++i? Doesn't it save memory and is one op faster?
I'm pretty sure the c++ compiler will optimize it to whichever is better anyway. But it's mostly force of habit, and changing it has never made a difference for me.
i know i m late but just want to know how u got a hint of some gcd concept in F?
Colin , do you have the habit of thinking while moving around ? Glad to know, because I thought good programmers just sit and think without a whiteboard? Do you use whiteboard for thinking
Yes, pacing helps me a lot as opposed to just sitting down. I use the whiteboard for doing out math and complex examples (and also for demonstrating my thoughts on div. 2 screencasts where I care less about speed), but I can usually visualize stuff pretty well in my head otherwise.
I also like the experience of jumping up and running back to the computer in excitement when I get an idea
@@ColinGalen yes..😆
@@ColinGalen 🥺
I'm curious do you have/had a a mentor to guide you on your comepetitive programming journey?
No, only friends that I wanted to beat
can you tell me how you run your text mate please?
Hey colin, was this round harder than usual div. 3 rounds? I managed to solve 3 problems in the last div 3 contest but could only do 1 in this one
I think B and C were pretty heavy implementation-wise, and they were probably harder than the old form of div. 3's. The round author's different for this one, so that probably explains it.
I think D and E1 are also worth a try though, even though they're later in the problem order (in particular, look at the solve count on E1)
@@ColinGalen ok thanks, Ill try those questions out!
Solved A
Your hair is beautiful besides your coding skills :)
Thank you for the explanations! Btw, I have encountered problems like D, but never found a good proof about why greedy works. Does anybody have it?
If you find a good proof, then please tell me too.
I was going to write out something in comments here. But it became super long, so I wrote it in a codeforces comment (notice that the "comment-844901" part isn't highlighted, that's youtube formatting screwing things up. I guess you should copy/paste the link directly instead of clicking on it.) - codeforces.com/blog/entry/95447?#comment-844901
Also, the editorial gives a proof, I think it's pretty good, but a little handwavy.
That's a really thorough analysis. I think it is very helpful for less skilled participants. Thanks for it and also for your content!
How do I make it when I type it to run cp % compr
And I was 1st in the Facebook hackercup at some point, but ended up 2700+
cracked af
omg, you are back !
for F, the trick of appending a + a, if we have a = 111, then a + a = 111111 and gives 6. so should we use this trick only when atleast one 0 is present?
It's fine if it's all 1's, then you know the answer is infinity.
Don't you get annoyed when people ask your age, age when you started cp, blah blah
Why the first sample is invalid?
What's your code forces I'd name
How old were u when u got introduced to cp??
I've heard that when he was born he ran off to the nearest computer in the hospital and started solving codeforces problems.
I don't comprehen why best[i][j] = d - 1;
First viewer.
I am not in your friend list. UwU
don't read too much into it