It's been a decent while since I did one of these. Speed still seems to be ok.

Solves:

• A @ 1 minute 6 sec. Very standard


• B @ 4 minute 4 sec. Also standard


• C @ 9 minute 10 sec. Wrote some montonic array & binary search


• D @ 14 minute 49 sec. DFS-like ordered sequence builder


• F @ 52 minute 12 sec. RMQ + range set segtree on sorted list

tags: programming atcoder contest-logs

"This ARC also serves as a qualification round to select the 18 contestants for the Japanese national finals, making it significantly more difficult than a regular ARC. Due to circumstances, we replaced the tasks and changed the point values. Since there are no easy tasks, the difficulty level of solving one or more tasks has increased. Please be careful. Since the difficulty level is flat, we recommend reading all the tasks and not necessarily solving them in order."

pov i forget to read this and consequently spend the entire contest on A (and fail to solve)

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tags: programming atcoder

This problem is from today's atcoder beginner contest

You are given a list A of lowercase English strings.
For each string S in A, solve the following problem:

You can perform two operations to S:

- Delete the last character of S (if it is non-empty)
- Add any lowercase character to the end of S

Find the minimum number of operations to convert S into either the empty string or a string that comes before it in A.

This kind of screams trie...

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tags: programming atcoder contest-logs

Took Atcoder Regular Contest 185 this morning. I had done one ARC virtual in the past, but that one had relatively more 'normal' questions than today's contest. I think it went alright? I don't really have a sense of scale with ARC yet.

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tags: programming atcoder contest-logs

I should put more effort into these surely...

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tags: programming atcoder contest-logs

Woke up 10 min before contest, slow start but wow.. good contest I think

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tags: programming atcoder contest-logs

vced ARC 058 w/ jasonwei

C was theoretically easy, construct from smallest digit, etc. but I messed up overflow case [twice] and that whole mess took like 30m total

D was fun combo, pathfinding nonsense that partition & track crossings kind of deleted

E was some DP that I failed, also managed to forget that complementary counting existed.. smh

didn't have anything substantial on F besides "knapsack" so ya

mid contest, definitely need to work on dp

tags: programming atcoder contest-logs

• A: trivial


• B: invert array, trivial


• C: trivial


• D: pretty cool, restructure directed graph as an undirected graph w/ directed weight, DFS


• E: possibly some sort of ranging and binary search, couldn't work out implementation


• F: tried to run the knapsack dp as normal but store a best_cost[] alongside, and attempted to use some quasi-convexity and 2p to speed up choice but this did not work (AC x53, WA x5)


• G: impossible wtf jasonwei orz

terrible perf lol. should I take the upcoming AGC? idk.

tags: programming atcoder contest-logs

Decent contest. Started 6 min late bc I lost track of time while debugging some cses problem :/ but it was fine..

ABC were basically trivial, C had a pretty simple pattern (provable by optimal-choice argument) which I got relatively quickly. D was an adventure, though.

Task essentially asks us to determine in a 2d bitfield the...

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tags: programming atcoder contest-logs

I did the ABC today: https://atcoder.jp/contests/abc369

The fumbling started on problem A, where I misread the input format and consequently got 2 WA (don't worry why this caused 2 WA and not 1). Then I did a dumb thing...

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tags: programming atcoder contest-logs