Quite delayed, but here we have stats about hacks in Codeforces Round 282 (Div. 2).
Previous posts can be found here, including div1.
Stats
Problem | Successful hacks | Unsuccessful hacks | Other | Sum | Solutions which can be hacked | Accepted solutions | All solutions on final tests |
---|---|---|---|---|---|---|---|
495A - Digital Counter | 623 (85.58%) | 76 (10.44%) | 29 (3.98%) | 728 | 47 (2.65%) | 1727 (97.35%) | 1774 |
495B - Modular Equations | 274 (79.42%) | 60 (17.39%) | 11 (3.19%) | 345 | 232 (27.17%) | 622 (72.83%) | 854 |
495C - Treasure | 103 (56.59%) | 75 (41.21%) | 4 (2.20%) | 182 | 426 (64.06%) | 239 (35.94%) | 665 |
495D - Obsessive String | 0 | 0 | 0 | 0 | 3 (27.27%) | 8 (72.73%) | 11 |
495E - Helping People | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Hacks and possible hacks description
495A - Digital Counter
That was an interesting problem, but the hacks were pretty simple — the pretests weren't checking every digits, so when someone made a mistake, we can make use of it.
Congratulation to all hackers, because only 47 solutions (2.65%) didn't pass final tests. :)
495B - Modular Equations
The most popular hack was pretty simple:
1000000000 1
Solutions with complexity O(|b - a|) resulted with TLE.
495C - Treasure
The hacks were simple strings with no solutions like:
(#(
(((#)((
(#(()
It was also test #14 (look below):
((#)(
Pretty and deadly :)
495D - Obsessive String
495E - Helping People
Fastest hackers
Problem | Time | Hacker | Defender | Hack |
---|---|---|---|---|
495A - Digital Counter | 0:11:52 | roiti46 | miloserd | 127885 |
495B - Modular Equations | 0:34:08 | gerelteiblog | YoChinezu | 128171 |
495C - Treasure | 0:49:03 | iphone | god_of_pain | 128488 |
Best hackers
Best rooms
Room | #hacks | Hackers |
---|---|---|
67 | 22 | ImagineWarrior [13], biltharesatyendra [7], mR_zohir [2] |
44 | 19 | ivan.sachkovski [9], smallling [9], D05T0N [1] |
48 | 18 | Bek13t [11], sxczf [4], aman_cold [3] |
8 | 17 | komendart [10], dinepo [5], zjwoody [2] |
29 | 17 | gerelteiblog [12], underSpirit [2], deleteeeeeeeeed [2], r3gz3n [1] |
59 | 17 | IDont_love_TanyaRomanova [15], Khairy [1], compilation_error [1] |
61 | 16 | deemem26 [13], shadow_crawler [3] |
4 | 15 | bulat.s [6], ruvamu [6], GreatDice [2], aloksharma [1] |
50 | 15 | sanzhar_001 [7], arystan_kalimov [5], M.Aladdin [3] |
68 | 15 | bonyisrail [10], zyaad [3], bes4etnov [2] |
72 | 15 | ezkatka [10], Rafiq_SEC [3], Arento [1], Alimol [1] |
How do you detect the country of contestants? I think there is something wrong.
For example hakeem is from Kazakhstan, not Iran.
Thanks for mentioning. I used to check everyone's country, but it looks like it is quite bugged. I will take a look.
thanks kostka for this information :)
I know this was probably asked before but I don't know where to look for, so what is other? Wrong inputs?
Also. One of the: INVALID_INPUT, GENERATOR_INCOMPILABLE, GENERATOR_CRASHED, IGNORED, OTHER.
And still, what is OTHER? (and ignored) :)
You have to ask Codeforces Team — I have never seen such thing :)
It is just in possibilities.
very nice...
wish to continue it...
and so nice to see Iran in top countries( I'm in the list too :) )