We will hold AtCoder Beginner Contest 265.
- Contest URL: https://atcoder.jp/contests/abc265
- Start Time: http://www.timeanddate.com/worldclock/fixedtime.html?iso=20220821T2100&p1=248
- Duration: 100 minutes
- Number of Tasks: 8
- Writer: Nyaan, kyopro_friends, PCTprobability, leaf1415, YoshikaMiyafuji
- Tester: Kodaman, PCTprobability
- Rated range: ~ 1999
The point values will be 100-200-300-400-500-500-600-600.
We are looking forward to your participation!
Great Contest! enjoyed it... Finally I can now become Cyan on atcoder as well :P
UPD: Became Cyan (1200+) :P
Now I can participate in AGCs as well.
have u done E i wrote dfs then tried memoizing it using map but haven't succeeded from tle
Yes, I solved E with DP. you may see my submission.
LOL. My approach is exactly same. Submission
pls name tasks next time like DP1, DP2, and so on
Agree. XD
Btw can you tell me how to solve F if you solved?
DP[i][d1][d2] = count of prefixes with d1 <= D and d2 <= D
you can go from DP[i][d1][d2] to DP[i+1][d1 + |x — pi][d2 + |x — qi|]
last part is prefix sums for fast transform
Since time limit is 6 second it actually works also without any prefix sums.
hmm, I added it because of tle with $$$O(n D^2 \times 1000)$$$
Your code fails after_contest tests
Yes, I saw that. Guess it my lucky day ;)
Did any other person get $$$20$$$ AC and $$$1$$$ TLE in $$$G$$$?
I did by applying brute force.
Nice contest again, thanks.
But text of B was not optimal. The "time limit" is actually not a time limit, but the remaining time. Usually if we need x time units to do a step, and remaining time is x, then it is ok to do the step. But here it was not, we needed timelimit=x+1. I needed 4 submission to understand.
New to atcoder, Apologies if its previously answered. Is there anyway we can see the testcase on which our code is failing?
There you go :)
Thank you, how much time does it take for a contest TCs to appear there?
From the current available test-cases, it's probably 2 to 3 weeks.
We realized tests of F are weak. (The code that generated tests contained a bug.) We added some tests like
99_after_contest_01.txt.Let’s get back to the original problem. This case, the possible values of (x,y) is relatively small, so we can solve it in a total of $$$O(N^3(logN+logM))$$$ time by storing the DP table in a dictionary. If you use a fast language, your code will be accepted.
Can someone explain why the possible values of (x, y) are relatively small in problem E??
While contest I assumed, since in each step we can make one of three choices, we can reach up to $$$3^n$$$ points.
But that is misleading, since there are only 3 kinds of steps, and order of the single steps does not matter, it is less than $$$n^3$$$ different points possible.
They can be described by dp[x][y][z] where $$$x+y+z\leq n$$$
But that is misleading, since there are only 3 kinds of steps, and order of the single steps does not matter, it is less than $$$n^3$$$ different points possible.
Can you explain this statement again? Thanks in advance.
I think it was my first time solving G in the new ABC format, really happy about that, no longer stuck between 1600 and 1700. and interesting problems overall.
There is an error in the problem statement for Ex (No-capture Lance Game)
It says "The first player can move the piece at (1,7) to (1,4), (1,5), or (1,6); the second player can move the piece at (3,4) to (3,1), (3,2), or (3,3). The first player cannot move the piece at (2,1).", but the piece at $$$(3,4)$$$ belongs to the first player.
Just realized (from Twitter) that sample input 3 of ABC 265 question C was not some random inputs. It is an ASCII art:
Move your head further away to see the ASCII art.
I hadn't noticed it at that time but I noticed it now. ABC 265 is hidden under the test case. Hats off to the author/tester for the test case.
Does anyone have idea about
? Seems to be O(n^2D)