Blog entries - Codeforces

#	User	Rating
1	tourist	3805
2	maroonrk	3637
3	Benq	3513
4	ecnerwala	3506
5	MiracleFaFa	3466
6	slime	3428
7	jiangly	3415
8	Radewoosh	3399
9	greenheadstrange	3393
10	djq_cpp	3391

#	User	Contrib.
1	awoo	192
2	-is-this-fft-	191
3	Monogon	185
4	Um_nik	182
4	YouKn0wWho	182
6	maroonrk	170
7	antontrygubO_o	168
8	errorgorn	166
8	kostka	166
8	SecondThread	166

MikeMirzayanov's blog

Me Too

By MikeMirzayanov, 8 days ago, In English

+1373

MikeMirzayanov
8 days ago
46

2021-2022 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred)

By MikeMirzayanov, 5 weeks ago, In English

Hello.

In the meantime, the onsite event has already begun. You can follow the results at the link https://nerc.itmo.ru/archive/2021/standings.html (refrain from viewing if you want to plan to write a mirror and want the conditions as close as possible to the participants in the competition).

There is great news. This year it was possible to get together without any online participation. Teams write from one computer! Good old ICPC.

And I suggest you join the online mirror. It is designed for team participation by those who have passed the qualifying competitions. Ready to try? Use the link: 2021-2022 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred).

Good luck!

Announcement of 2021-2022 ICPC, NERC, Northern Eurasia Onsite (Unrated, Online Mirror, ICPC Rules, Teams Preferred)

nerc, icpc, neerc

+205

MikeMirzayanov
5 weeks ago
20

About CodeTON Round 1 Prizes Strikes Again

By MikeMirzayanov, 6 weeks ago, In English

Hello.

I started processing responses on the form where we collected your TON wallet addresses. Unfortunately, many winners did not complete the form. I contacted some of them in PM and it turned out that this was not intentional.

We are extending the deadline for completing the form until 2022-04-06 23:59:59 (UTC +3). Please, if you want to receive coins, then fill out the form. A valid address looks like a random 48-character string. To register a wallet, follow one of these links: https://tonkeeper.com/ or https://wallet.ton.org/

The form can be filled out at https://codeforces.com/userForm/203c74605996e40f

Coins will be received by those who are at the top-1000. Additionally, those who solved at least one problem in this round will receive 1 coin each. Details can be read at the link.

The form will be processed on April 7th. And in a week after it, we will send out coins. Please do not disturb me or the organizers with questions that are answered in this post.

Also I remind you about TON Smart Challenge contest aimed at contract source code optimization: https://t.me/toncontests/26 It's not too late to connect and try your hand

You can read more about this competition here:

TON Smart Challenge 1 →

codeforces, ton

+108

MikeMirzayanov
6 weeks ago
19

Help from NEAR for Our Community

By MikeMirzayanov, 7 weeks ago, In English

Hello, Codeforces.

We live in difficult times. And, unfortunately, our community is highly dependent on world events around us. Three years ago, it seemed easy to send a t-shirt anywhere in the world. Now it's a quest with many unknowns. Just a few months ago, it was not difficult to send a reward to the problem writer. But now, we are cut off from the outside world and regulated by multiple new laws.

And here it is very important not to lose, not to break what has already been done. Don't stand still, move forward. I am very glad and grateful to the problem writers and coordinators that in March we managed to hold 10 ratings (we held 9, come to participate in the tenth). Thanks to everyone who took part in the preparation!

And I want to share another great news. Our friends NEAR has come up with the initiative to support the community during this difficult time. We are pleased to announce that the upcoming rounds will be funded by NEAR, which will help with the payment of rewards to problem writers and coordinators. This is a timely and important help. Thanks!

It will be easier and faster for us if the problem writers or coordinators have the opportunity to accept a reward in the form of a cryptocurrency transfer. In this case, we are ready to transfer 25% more and make the transfer much faster. Oh, it's a pity we can't send t-shirts with crypto.

And I remind you that the next round (and Codeforces Round #780 (Div. 3)) is waiting for you) will take place very soon, on Mar/31/2022 17:35 (Moscow time). I hope to see you among the participants.

— Mike

near, codeforces, help

+997

MikeMirzayanov
7 weeks ago
13

About CodeTON Round 1 Prizes

By MikeMirzayanov, 7 weeks ago, In English

TLTR: If you are in the top-1000 of CodeTON Round 1, then fill out the form by the link https://codeforces.com/userForm/203c74605996e40f. Also, anyone who solved at least one problem in the round can fill out it and get 1 TON airdrop. The deadline is 23:59:59 (UTC +3) 04.04.22.

Hello. Great news from the TON Team. I give them the floor.

Good news everyone!

We decided to celebrate the successful finish of the CodeTON round by airdropping all the people who have solved at least one of the problems (officially, practice and virtual participation don't count) of the CodeTON round. Such participants are eligible for 1 TON airdrop and a memorable NFT. Please do note that such NFT bears only symbolic value and is not entered to have any financial or investment value.

Please submit your TON wallet address via the link https://codeforces.com/userForm/203c74605996e40f if you are eligible for such an airdrop by 23:59:59 (UTC +3) 04.04.22.

Winners are more than welcome to provide organizers with the TON Wallet addresses to claim their prizes.

We also want to invite all of you to try yourself at TON Smart Challenge contest aimed at contract source code optimization: https://t.me/toncontests/26

You can read more about this competition here:

TON Smart Challenge 1 →

Thank you for taking your part, hope you enjoyed the round, looking forward to meeting you later!

TON Foundation

ton

+339

MikeMirzayanov
7 weeks ago
29

No War!

By MikeMirzayanov, 2 months ago, In English

I can't write for the entire Codeforces, because this community consists of different people and opinions. I will write for myself. I have two children — my sunshine daughter Tanechka and Codeforces. Recently I talked with Tanya and called what is happening a catastrophe, a big evil, and pain. As a child, I was brought up that war is the greatest of tragedies. So I repeat this to my second child. No war! I dream of waking up in a world where people don't hide in bomb shelters. The offensive of the Russian troops is a terrible dream and a nightmare. The government has given the order, and now people are dying, families are being torn apart and cities are being destroyed. Geopolitical ambitions are above all. It would seem that civilization is here it is, but troubled wild times have come again. Ukraine is a sovereign free country, our friends and colleagues are there.

nowar

+3467

MikeMirzayanov
2 months ago
133

Codeforces Global Rounds 2021: Final Results (GR13-GR18)

By MikeMirzayanov, 3 months ago, In English

Tomorrow will be the first global round of this year. And we are happy to sum up the results of last season. We announce the results!

We remind you that the global rounds are a joint initiative of XTX and Codeforces. We are happy to announce that they continue into the new year.

We hold 6 such rounds per year. All of them are open to both divisions. At each such round, 50 brand T-shirts were handed out, and we are happy to give T-shirts to all problem authors.

The prizes for the 6-round series are:

In each round top-100 participants get points according to the table.
The final result for each participant is equal to the sum of points he gets in the four rounds he placed the highest.
The best 20 participants over all series get sweatshirts and place certificates.

The final standings after six rounds (sorted by total points in four best placed rounds):

Place	Contestant	=	GR 13	GR 14	GR 15	GR 16	GR 17	GR 18
1	Radewoosh	3291	291	1000	—	1000	1000	291
2	tourist	2815	135	403	1000	706	706	346
3	ksun48	2201	135	706	706	443	346	265
4	maroonrk	1894	1000	226	142	226	265	403
5	Petr	1730	575	—	497	—	575	83
6	Benq	1662	—	497	575	346	—	244
7	jiangly	1501	497	346	63	497	161	4
8	Um_nik	1199	176	575	346	102	34	—
9	dengyaotriangle	1094	—	—	—	—	94	1000
10	DmitryGrigorev	1065	706	—	176	70	54	113
11	duality	1045	277	371	186	211	—	—
12	Golovanov399	1017	254	277	138	—	325	161
13	tatyam	969	—	291	161	325	29	192
14	hos.lyric	888	128	—	254	—	181	325
15	lumibons	871	325	—	265	—	176	105
16	aid	868	226	145	218	198	226	29
17	Subconscious	812	—	—	171	125	403	113
18	slime	767	—	—	—	192	—	575
19	sunset	742	371	—	371	—	—	—
20	gisp_zjz	725	—	153	198	60	277	97
21	yosupo	724	—	—	4	—	14	706
22	SSRS_	715	68	90	31	—	186	371
23	dlalswp25	707	204	161	—	131	211	92
24	QAQAutoMaton	700	—	—	—	575	—	125
25	kotatsugame	659	—	149	105	277	—	128
26	hitonanode	657	—	181	62	307	107	8
26	qazswedx2	657	403	—	—	—	—	254
28	Ormlis	642	—	171	48	235	149	87
29	inaFSTream	641	—	—	—	—	198	443
30	never_giveup	626	218	192	74	—	142	58
31	mhq	625	—	218	291	116	—	—
32	LayCurse	622	149	265	192	—	16	—
33	He_Ren	582	—	—	—	371	131	80
34	natsugiri	574	—	166	110	80	218	—
35	mango_lassi	555	119	135	97	204	11	—
36	LJC00118	523	198	325	—	—	—	—
36	dreamoon_love_AA	523	—	52	307	72	92	37
38	Maksim1744	517	54	244	66	153	—	—
39	greenheadstrange	515	—	72	443	—	—	—
40	yhx-12243	511	—	443	68	—	—	—
41	nuip	499	—	—	166	90	171	72
42	ABitstOCHASTIC	497	—	—	—	—	—	497
42	he_____hezhou	497	—	—	—	—	497	—
44	SpyCheese	489	—	—	46	—	443	—
44	snuke	489	—	—	27	218	244	—
46	ugly2333	484	—	138	54	—	74	218
47	Toxel	468	90	—	76	—	254	48
48	AndreySergunin	444	244	78	122	—	—	—
49	RALZH	443	443	—	—	—	—	—
50	hank55663	420	—	—	—	63	235	122
51	NotaMotuaQAQ	417	110	307	—	—	—	—
52	TadijaSebez	408	—	5	403	—	—	—
53	Alice_foo_foo	403	—	—	—	403	—	—
54	Endagorion	399	211	1	17	—	166	5
55	Farhod_Farmon	397	153	102	—	142	—	—
56	ecnerwala	391	346	—	45	—	—	—
57	hanbyeol_	390	—	—	—	291	99	—
58	dorijanlendvaj	385	10	—	52	166	—	157
59	zh0ukangyang	383	—	—	—	—	157	226
60	blackbori	377	—	83	50	244	—	—
61	huyinghao0706	371	—	—	—	—	371	—
62	sansen	370	—	—	116	254	—	—
63	TLEwpdus	362	—	2	211	—	—	149
64	Heltion	351	235	116	—	—	—	—
65	dario2994	350	94	128	—	58	—	70
66	tmwilliamlin168	348	—	41	—	—	307	—
67	turmax	339	—	142	119	78	—	—
68	ko_osaga	325	—	—	325	—	—	—
69	Karry5307_AK_NOI2022	321	—	—	—	—	110	211
70	TLE	320	—	—	—	149	—	171
71	heno239	312	—	176	70	—	—	66
72	p_b_p_b	307	307	—	—	—	—	—
72	353cerega	307	52	—	153	—	102	—
72	HIR180	307	—	—	—	—	—	307
75	Marcin_smu	301	265	—	—	—	36	—
76	receed	300	102	198	—	—	—	—
77	Alan233	299	—	—	—	—	113	186
78	tute7627	297	—	27	58	—	70	142
79	Froggygua	291	—	—	—	—	291	—
80	fanache99	288	—	131	—	105	52	—
81	Isonan	281	107	157	—	—	17	—
82	KostasKostil	277	—	—	277	—	—	—
82	ideology	277	—	—	—	—	—	277
84	jiangly_fan	273	—	—	157	116	—	—
85	Rafbill	272	80	—	—	87	105	—
86	mtsd	269	—	—	—	—	138	131
87	fivedemands	265	—	—	—	265	—	—
88	risujiroh	262	58	—	—	—	—	204
89	_menhera	257	—	22	—	—	—	235
89	Temotoloraia	257	—	—	226	10	21	—
91	Elegia	254	—	254	—	—	—	—
92	gs18115	252	—	—	—	—	192	60
93	Egor	244	—	—	244	—	—	—
93	AliShahali1382	244	85	24	135	—	—	—
95	l1ll5	238	34	—	—	—	204	—
95	atomicenergy	238	46	16	—	—	135	41
97	kotamanegi	235	—	—	235	—	—	—
97	_h_	235	—	235	—	—	—	—
99	noimi	225	—	94	34	97	—	—
100	potato167	216	—	—	37	22	58	99
101	kmjp	215	—	—	22	27	116	50
101	AutumnKite	215	—	—	—	—	153	62
103	Argentina	212	—	—	—	186	—	26
104	ehnryx	211	—	211	—	—	—	—
105	eatmore	210	116	—	—	—	—	94
106	WangZhikun	204	—	204	—	—	—	—
106	renascencepjw0510	204	—	—	204	—	—	—
108	wasa855	202	—	—	—	26	—	176
108	fastmath	202	92	110	—	—	—	—
108	amethyst0	202	181	—	21	—	—	—
111	errorgorn	199	—	—	43	—	78	78
112	Froggay	198	—	—	—	—	—	198
113	ainta	195	—	—	—	—	119	76
114	uwi	192	192	—	—	—	—	—
115	Geothermal	188	—	—	—	157	31	—
116	nantf	186	—	186	—	—	—	—
116	YeongTree	186	186	—	—	—	—	—
118	voidmax	181	—	—	—	181	—	—
118	Rainbow_qwq	181	—	—	—	—	—	181
118	scott_wu	181	—	—	181	—	—	—
121	Torta	177	—	—	80	—	97	—
122	nick452	176	—	—	—	176	—	—
123	fedoseev.timofey	174	39	63	72	—	—	—
124	ccf_n0i	171	—	—	—	171	—	—
124	MAOooOAM	171	171	—	—	—	—	—
126	_--_-__-	166	166	—	—	—	—	—
126	PetelgeuseRomaneeconti	166	—	—	—	—	—	166
128	Nachia	164	138	—	26	—	—	—
129	Anadi	161	161	—	—	—	—	—
129	huhaoo	161	—	—	—	161	—	—
131	Ra16bit	158	66	—	—	92	—	—
132	dsgrekova2	157	157	—	—	—	—	—
132	peti1234	157	—	125	—	32	—	—
134	krijgertje	153	—	119	—	—	—	34
134	Y25t	153	—	—	—	—	—	153
136	Egor.Lifar	152	—	8	16	128	—	—
137	isaf27	150	63	—	87	—	—	—
138	Swistakk	149	—	—	149	—	—	—
139	Amoo_Safar	145	—	—	145	—	—	—
139	__fishingprince__	145	—	—	—	—	145	—
139	_FireBladeMaster_	145	—	—	—	—	—	145
139	137_345_2814	145	—	—	—	145	—	—
139	mnaeraxr	145	145	—	—	—	—	—
144	abc864197532	144	—	—	125	—	—	19
144	saba2000	144	125	—	19	—	—	—
146	ppavic	142	142	—	—	—	—	—
147	m_99	141	22	—	—	119	—	—
148	Xellos	140	—	92	—	48	—	—
149	neal	138	—	—	—	—	—	138
149	wuwuwu	138	—	—	—	138	—	—
151	crackersamdjam	135	—	—	—	135	—	—
151	gyh20	135	—	—	—	—	—	135
151	conqueror_of_tourist	135	50	37	—	—	48	—
154	flashmt	131	—	—	94	—	37	—
154	syvjjp416	131	—	—	131	—	—	—
156	oleh1421	130	—	4	—	94	—	32
157	qwerty787788	128	—	—	128	—	—	—
157	Zhtluo	128	—	—	—	—	128	—
159	Noam13	126	2	—	2	122	—	—
160	Melania	125	—	—	—	—	125	—
161	AlesyaIvanova	124	—	74	—	50	—	—
162	Arayi	122	122	—	—	—	—	—
162	Hazyknight	122	—	122	—	—	—	—
162	djq_cpp	122	—	—	—	—	122	—
165	Suiseiseki	119	—	—	—	—	—	119
166	yuyue	116	—	—	—	—	—	116
166	Merkurev	116	—	—	—	116	—	—
168	simonlindholm	113	—	—	113	—	—	—
168	Yongaron	113	—	113	—	—	—	—
168	chenyanbo	113	113	—	—	—	—	—
171	Pyqe	108	—	45	—	63	—	—
172	Itst_boyfriend	107	—	—	107	—	—	—
172	Tiramister	107	—	107	—	—	—	—
172	asdsasd	107	—	—	—	107	—	—
172	rama_pang	107	—	—	—	—	—	107
176	Wu_Ren	105	105	—	—	—	—	—
176	ix35	105	—	105	—	—	—	—
178	Alex_2oo8	102	—	—	102	—	—	—
178	chi1012	102	—	—	—	—	—	102
180	antontrygubO_o	99	—	99	—	—	—	—
180	krismaz	99	—	—	99	—	—	—
180	tabr	99	—	—	—	99	—	—
180	Comet_Honeymoon	99	99	—	—	—	—	—
184	Vercingetorix	97	—	—	—	—	41	56
184	donentseto	97	97	—	—	—	—	—
184	Suika_predator	97	—	97	—	—	—	—
187	BurnedChicken	96	—	—	60	29	7	—
188	Kodaman	92	—	—	92	—	—	—
189	LiciaDu	90	—	—	90	—	—	—
189	ljcleo	90	—	—	—	—	90	—
189	TeaPot	90	76	—	14	—	—	—
189	Kubic	90	—	—	—	—	—	90
193	Aishiteru.	87	87	—	—	—	—	—
193	Enchom	87	—	87	—	—	—	—
193	antekb	87	—	—	—	—	87	—
196	God_Of_Blunder	85	—	—	—	85	—	—
196	voover	85	—	—	85	—	—	—
196	sumitacchan	85	—	85	—	—	—	—
196	sys.	85	—	—	—	—	—	85
196	Skyqwq	85	—	—	—	—	85	—
201	szhlg	83	83	—	—	—	—	—
201	skywalkert	83	—	—	83	—	—	—
201	emptyhope	83	—	—	—	—	83	—
201	ezLadder	83	—	—	—	83	—	—
205	djq_fpc	80	—	80	—	—	—	—
205	Roundgod	80	—	—	—	—	80	—
207	SirShokoladina	78	78	—	—	—	—	—
207	scli_weapon	78	—	—	78	—	—	—
209	C.S.T.T	76	—	—	—	76	—	—
209	AoLiGei	76	—	—	—	76	—	—
209	orzdevinwang	76	—	76	—	—	—	—
209	dXqwq	76	—	—	—	—	76	—
213	PinkieRabbit	74	—	—	—	—	—	74
213	prick	74	74	—	—	—	—	—
213	IntoTheNight	74	—	17	56	—	1	—
216	szb	72	72	—	—	—	—	—
216	KevinWan	72	—	—	—	—	72	—
218	zscoder	71	37	—	—	34	—	—
219	hamlet	70	70	—	—	—	—	—
219	timmyfeng	70	—	70	—	—	—	—
221	est_stella	68	—	—	—	—	—	68
221	happyguy656	68	—	—	—	—	68	—
221	veckoper	68	—	68	—	—	—	—
221	Izumi_Chiaki	68	—	—	—	68	—	—
225	ynsm	66	—	66	—	—	—	—
225	awoo	66	—	—	—	66	—	—
225	K_T_O	66	—	—	—	—	66	—
228	Rubikun	63	—	39	—	—	24	—
228	Kalptaru	63	—	—	—	—	63	—
228	YLWang	63	—	—	—	—	—	63
228	AnandOza	63	36	—	—	—	—	27
232	jonathanirvings	62	—	—	—	—	62	—
232	jcvb	62	62	—	—	—	—	—
232	izone	62	—	62	—	—	—	—
235	AlexLuchianov	60	—	60	—	—	—	—
235	20I6wudi	60	—	—	—	—	60	—
235	saketh	60	60	—	—	—	—	—
238	Monogon	58	—	58	—	—	—	—
238	peltorator	58	58	—	—	—	—	—
240	SolarPea	56	—	—	—	—	56	—
240	tfg	56	—	—	—	56	—	—
240	Quirrel	56	—	56	—	—	—	—
243	balbit	54	—	—	—	—	—	54
243	Pa.Nic	54	—	54	—	—	—	—
243	NeoOrgano	54	—	—	—	54	—	—
246	alireza_kaviani	52	—	—	—	52	—	—
246	lzoi.win	52	—	—	—	—	—	52
248	s_r_f	50	—	50	—	—	—	—
248	icypiggy	50	—	—	—	—	50	—
250	_Ash__	48	—	48	—	—	—	—
250	Shibuyap	48	48	—	—	—	—	—
252	mshcherba	46	—	46	—	—	—	—
252	Barichek	46	—	—	—	46	—	—
252	yspm	46	—	—	—	—	46	—
252	PuRpLe_FoReVeR	46	46	—	—	—	—	—
252	maspy	46	—	—	—	—	—	46
257	wifiiii	45	—	—	—	45	—	—
257	Gary	45	—	—	—	45	—	—
257	LMOliver	45	—	—	—	—	45	—
257	physics0523	45	—	—	—	—	—	45
261	zhangzy	43	—	43	—	—	—	—
261	suyiheng	43	—	—	—	—	—	43
261	xuanyi	43	43	—	—	—	—	—
261	arvindf232	43	—	—	—	—	43	—
265	MofK	42	—	—	—	—	26	16
266	lucaperju	41	—	—	—	41	—	—
266	jiangIy	41	—	—	41	—	—	—
266	doped.silicon	41	41	—	—	—	—	—
266	shennong	41	—	—	—	41	—	—
270	shb	39	—	—	—	—	39	—
270	kostia244	39	—	—	—	—	—	39
270	Maripium	39	—	—	39	—	—	—
273	cheissmart	37	—	—	—	37	—	—
273	stevenkplus	37	—	—	37	—	—	—
275	Wailydest	36	—	—	—	—	—	36
275	leaf1415	36	—	36	—	—	—	—
275	klimoza	36	—	—	—	36	—	—
278	Iscream2001	34	—	34	—	—	—	—
279	Bellalabella	32	32	—	—	—	—	—
279	soltanbh	32	—	32	—	—	—	—
279	olmrgcsi	32	—	—	32	—	—	—
279	Sung.An	32	—	—	—	—	32	—
283	ildth	31	—	31	—	—	—	—
283	EndSinger	31	—	—	—	31	—	—
283	FluffyT	31	31	—	—	—	—	—
283	MonkeyKing	31	—	—	—	—	—	31
287	Nyaan	29	—	—	29	—	—	—
287	amnesiac_dusk	29	29	—	—	—	—	—
287	Marckess	29	—	29	—	—	—	—
290	dragonslayerintraining	27	27	—	—	—	—	—
290	Nebuchadnezzar	27	—	—	—	—	27	—
292	catupper	26	26	—	—	—	—	—
292	Tlatoani	26	—	26	—	—	—	—
294	A-SOUL_Bella	24	—	—	—	—	—	24
294	KeNaj712	24	—	—	24	—	—	—
294	ALILILILILI-KHAN	24	—	—	—	24	—	—
294	Zayin	24	24	—	—	—	—	—
298	hotpotcondiment	22	—	—	—	—	—	22
298	16silver	22	—	—	—	—	22	—
300	sava-cska	21	21	—	—	—	—	—
300	sugarrr	21	—	—	14	—	—	7
300	sd0061	21	—	21	—	—	—	—
300	loveye	21	—	—	—	—	—	21
300	yuto1115	21	—	—	—	21	—	—
305	w0nsh	19	19	—	—	—	—	—
305	rniya	19	—	—	—	19	—	—
305	S2speed	19	—	—	—	—	19	—
305	almogwald	19	—	19	—	—	—	—
309	1092515504	17	—	—	—	—	—	17
309	HoshimiOWO	17	17	—	—	—	—	—
309	xay5421	17	—	—	—	17	—	—
312	C137	16	16	—	—	—	—	—
312	VladProg	16	—	—	—	16	—	—
314	CXY007	14	—	—	—	—	—	14
314	Nero	14	—	14	—	—	—	—
314	dendi239	14	14	—	—	—	—	—
314	cuom1999	14	—	—	—	14	—	—
318	olphe	13	—	—	—	13	—	—
318	yyljkydr	13	—	13	—	—	—	—
318	eecs	13	—	—	—	—	—	13
318	SW2000	13	13	—	—	—	—	—
318	PaiGuGou	13	—	—	—	—	13	—
323	Akulyat	12	—	—	7	5	—	—
324	_Guoyh_	11	—	—	—	—	—	11
324	Yukikaze_	11	—	11	—	—	—	—
324	wiwitrifai	11	11	—	—	—	—	—
324	JeanBombeur	11	—	—	—	11	—	—
324	Atreus	11	—	—	11	—	—	—
329	Obsidian	10	—	—	10	—	—	—
329	Laurie	10	—	—	—	—	10	—
329	al3xstr33t	10	—	10	—	—	—	—
329	xwp	10	—	—	—	—	—	10
333	Ali.Kh	8	—	—	8	—	—	—
333	nweeks	8	—	—	—	8	—	—
333	magga	8	8	—	—	—	—	—
333	Kostroma	8	—	—	—	—	8	—
337	EnAnimant	7	7	—	—	—	—	—
337	Nots0fast	7	—	—	—	7	—	—
337	zyb	7	—	7	—	—	—	—
340	NoLongerRed	5	—	—	5	—	—	—
340	kamer	5	—	—	—	—	5	—
340	craborac	5	5	—	—	—	—	—
343	TheScrasse	4	—	—	—	—	4	—
343	tin-jyu	4	4	—	—	—	—	—
343	strongerthanspeed	4	—	—	—	4	—	—
346	iaNTU	3	—	—	1	—	2	—
347	dfcmd	2	—	—	—	2	—	—
347	caoyue	2	—	—	—	—	—	2
349	Jlytxdy	1	1	—	—	—	—	—
349	Werner_Yin	1	—	—	—	—	—	1
349	GRT_2018	1	—	—	—	1	—	—

globals, global rounds 2021, xtx

+194

MikeMirzayanov
3 months ago
0

About Unrated Educational Codeforces Round 121

By MikeMirzayanov, 4 months ago, In English

Hello, Codeforces.

Unfortunately, we have to declare the round unrated.

Absolutely, these are not issues of the side of Codeforces code, but rather it is a hardware issue. Probably, electricity, power unit or something else. This led to unexpected repeated reboots of the server with the database. I hope that we will be able to quickly deal with this.

We apologize to the writers of the round and its participants.

P.S. Please, do not downvote the round announcement: the writers are not to blame for what happened. And in general, this time it is difficult to blame someone. Sometimes hardware fails.

Mike.

unrated

+1497

MikeMirzayanov
4 months ago
111

I am Mike Mirzayanov. AMA!

By MikeMirzayanov, 4 months ago, In English

But why not!

Many people here seem to know me. Or maybe not quite? I am ready to answer your questions. Ask me anything! I plan to spend no more than 3 hours on answers. Sorry if I can't answer all the questions.

Let's more or less follow the rules from here https://www.reddit.com/r/IAmA/wiki/index

Below is actually a quote from the rules.

The interviewee begins the process by starting a post, describing who they are and what they do. Then commenters from across the internet leave questions and can vote on other questions according to which they would like to see answered.

The interviewee can go through and reply to the questions they find interesting and easily see those questions the internet is dying to have the answer to.

Because the internet is asking the questions, they're going to be a mix of serious and lighthearted, and you'll find yourself sharing all kinds of things you won't find in a normal interview.

Comments will be removed under a few circumstances:

Abusive or harassing comments.
Requests for personal favors from the OP (For example, "OP, can you send me a signed autograph").
Top-level comments must ask a question.
Comments where there would be no possibility of a real answer, especially where it is deliberately creepy or offensive.
"I bet OP won't answer this"-type responses, which usually come after the OP has finished responding to questions.
"Fluff," non-contributing responses from users, responding to all of the OP's comments for karma/attention.
Repeatedly asking the same question.

Please, don't attempt to bypass the rules by adding a ? to a nonquestion.

Questions must be directed toward the individual(s) doing the IAMA.

Under our policies, astroturfing is the practice of an individual or group of individuals who plant questions in an IAmA post for a particular purpose. This kind of behavior is forbidden.

UPD 1: Oh, I'm kind of tired of doing this. Please keep asking questions. Tomorrow I will answer again. Don't forget to vote for the most interesting ones. I will not have time to answer everything, I will choose something. Thanks!

UPD 2:

ama, iama, codeforces, mikemirzayanov

+1062

MikeMirzayanov
4 months ago
286

#	Post	Votes	Author
1	The Ultimate Topic List (with Resources, Problems and Templates)	4383	YouKn0wWho
2	Codeforces Round #752	3156	YouKn0wWho
3	User activity in the profile! [new, Feb. 2021]	3055	geranazavr555
4	Codeforces Round #712	2866	Monogon
5	Codeforces Round #733 (Div. 1 + Div. 2)	2795	tourist
6	Codeforces Round #735 (Div. 2)	2167	YouKn0wWho
7	Things I don't know	1965	Um_nik
8	My opinion on how to practice competitive programming	1899	Radewoosh
9	Goodbye 2021. Hello 2022!	1849	MikeMirzayanov
10	Corruption, Cheating at ICPC Yinchuan	1685	NXIST_buster
11	Codeforces Global Round 14	1595	FieryPhoenix
12	Evidence of ACPC Corruption	1547	ACPC_Corruption
13	C++20 Is Released	1524	MikeMirzayanov
14	Codeforces Round #743 Is Unrated: Investigating the Reason	1522	MikeMirzayanov
15	I compiled a list of almost all useful blogs ever published on Codeforces [update: till 09.06.2021]	1500	parveen1981
16	New Year Gift: Codeforces Catalog — Early Access	1448	MikeMirzayanov
17	Codeforces: Results of 2020 [list some changes and improvements]	1394	MikeMirzayanov
18	Codeforces Round #715	1371	Kuroni
19	Giving negative feedback to contests in comments	1347	antontrygubO_o
20	(The Ultimate) Code Library	1334	YouKn0wWho
21	Where are my pants	1323	sus
22	Codeforces Round #736	1253	Agnimandur
23	On Problems vs. Questions in Competitive Programming: My solution	1178	Sexpert
24	Competitive Programming Hall of Fame — cphof.org	1176	Ra16bit
25	Codeforces Round #732	1175	AquaMoon
26	Codeforces Round #722	1145	AmShZ
27	Codeforces Global Round 13	1092	star_xingchen_c
28	Polygon Updates (June — August 2021)	1013	unreal.eugene
29	Codeforces Round #742 (Div. 2)	967	ScarletS
30	Codeforces Round #741. How contest author is entertaining.	950	Wind_Eagle
31	Codeforces Round #723 (Rated for Div 2)	923	errorgorn
32	Petition to make (onsite part of) ICPC WF 2020 1-computer	914	Um_nik
33	Cheater Report in Global Round 15	910	kostka
34	Codeforces Round #703 (Div. 2)	908	okwedook
35	Codeforces Round #743	878	Markadiusz
36	Why didn't anyone tell me that Petr was in the Vatican?	872	Franchesco_virgoliniiii
37	[Tutorial] GCC Optimization Pragmas	854	nor
38	See your Codeforces 2021 Journey!!	830	abdude824
39	Discussion: Modern G++ Command Line	830	MikeMirzayanov
40	Codeforces Global Round 15	823	dario2994
41	China team won the IOI2021	820	Fuyuki
42	Codeforces Round #698 (Div.1, Div.2)	816	Nezzar
43	Codeforces Round #746 (Div. 2)	806	Hemose
44	Codeforces Round #754 (Div. 2)	805	JeevanJyot
45	Codeforces Round #745 Editorial	799	interlude
46	VK Cup 2021 — Final (Engine) and Codeforces Round #740	798	tourist
47	Codeforces Round #738 (Div. 2)	796	Bazoka13
48	Codeforces Round #708	781	shishyando
49	April Fools Day Contest 2021	781	Nickolas
50	Codeforces Round #761 (Div. 2)	773	dbsic211

Markup Use square brackets instead of round	Result
Simple likes widget `(likes:1)`
Same keys means same likes widgets `(likes:2)` `(likes:2)`
Same keys and different groups can be used for exclusive choices `(likes:3,option1)` `(likes:3,option2)`

Change Handle Feature

Hurry! Only until the 10th of January, you can change your handle (but only once)! Note that it will be possible to roll back the changes or change the handle again only after a year. Be careful what you wish for.

You can change your handle to the new one which wasn't used before by anybody or which was used by you before. The links to a profile page with an old handle would automatically redirect to the actual profile.

Again, this year if you took part in at least 10 rounds you can request a handle of an inactive participant. It means that the participant should have a period of activity on Codeforces of at most 180 days, this period should be in 2019 or earlier. The inactive participant can't have posted comments, messages, and so on. It can't take part in more than 2 contests. It will be automatically renamed and informed by email. A user has the opportunity to request back his/her handle: in this case, we will roll back the change and return your previous handle to you. If you can't change your handle to another, it means that some requirements don't meet. Please do not ask me to do something with it. Especially, I do not like requests like "this is my second account, I took an interesting handle myself". I'm not Santa Claus.

Talking about handles I always
reminisce the following story. Once a user wrote me the message: "Please change my handle from I_love_Valya to I_love_Sveta, as I no longer love Valya ..."

New Year's Masquerade of Colors and Ranks

The traditional magical tab has appeared in the profile setting. Happy New Year!

new year, happy new year, 2022

+1867

MikeMirzayanov
5 months ago
198

Codeforces Global Rounds 2021: Current Results (GR13-GR17)

By MikeMirzayanov, 5 months ago, In English

In 2021 (as in 2019 and 2020), with the support of XTX Markets, 6 rounds of the new Codeforces Global Rounds are held: common rounds for both divisions of 7–9 problems each. The duration of the rounds is 2-3 hours, depending on the number and complexity of the problems. All such rounds are rated for all participants. At each such round, 50 brand T-shirts are handed out, and we are happy to give T-shirts to all problem authors.

The prizes for the 6-round series in 2021:

In each round top-100 participants get points according to the table.
The final result for each participant is equal to the sum of points he gets in the five rounds he placed the highest.
The best 20 participants over all series get sweatshirts and place certificates.

Current standings after five rounds (sorted by total points in four best placed rounds):

Place	Contestant	=	GR 13	GR 14	GR 15	GR 16	GR 17
1	Radewoosh	3291	291	1000	—	1000	1000
2	tourist	2815	135	403	1000	706	706
3	ksun48	2201	135	706	706	443	346
4	maroonrk	1717	1000	226	142	226	265
5	Petr	1647	575	—	497	—	575
6	jiangly	1501	497	346	63	497	161
7	Benq	1418	—	497	575	346	—
8	Um_nik	1199	176	575	346	102	34
9	duality	1045	277	371	186	211	—
10	DmitryGrigorev	1006	706	—	176	70	54
11	Golovanov399	994	254	277	138	—	325
12	aid	868	226	145	218	198	226
13	tatyam	806	—	291	161	325	29
14	lumibons	766	325	—	265	—	176
15	sunset	742	371	—	371	—	—
16	dlalswp25	707	204	161	—	131	211
17	Subconscious	699	—	—	171	125	403
18	gisp_zjz	688	—	153	198	60	277
19	hitonanode	657	—	181	62	307	107
20	never_giveup	626	218	192	74	—	142
21	mhq	625	—	218	291	116	—
22	LayCurse	622	149	265	192	—	16
23	Ormlis	603	—	171	48	235	149
24	QAQAutoMaton	575	—	—	—	575	—
25	natsugiri	574	—	166	110	80	218
26	hos.lyric	563	128	—	254	—	181
27	mango_lassi	555	119	135	97	204	11
28	kotatsugame	531	—	149	105	277	—
29	LJC00118	523	198	325	—	—	—
29	dreamoon_love_AA	523	—	52	307	72	92
31	Maksim1744	517	54	244	66	153	—
32	greenheadstrange	515	—	72	443	—	—
33	yhx-12243	511	—	443	68	—	—
34	He_Ren	502	—	—	—	371	131
35	he_____hezhou	497	—	—	—	—	497
36	SpyCheese	489	—	—	46	—	443
36	snuke	489	—	—	27	218	244
38	AndreySergunin	444	244	78	122	—	—
39	RALZH	443	443	—	—	—	—
40	nuip	427	—	—	166	90	171
41	Toxel	420	90	—	76	—	254
42	NotaMotuaQAQ	417	110	307	—	—	—
43	TadijaSebez	408	—	5	403	—	—
44	Alice_foo_foo	403	—	—	—	403	—
44	qazswedx2	403	403	—	—	—	—
46	Farhod_Farmon	397	153	102	—	142	—
47	Endagorion	395	211	1	17	—	166
48	ecnerwala	391	346	—	45	—	—
49	hanbyeol_	390	—	—	—	291	99
50	blackbori	377	—	83	50	244	—
51	SSRS_	375	68	90	31	—	186
52	huyinghao0706	371	—	—	—	—	371
53	sansen	370	—	—	116	254	—
54	Heltion	351	235	116	—	—	—
55	tmwilliamlin168	348	—	41	—	—	307
56	turmax	339	—	142	119	78	—
57	ko_osaga	325	—	—	325	—	—
58	p_b_p_b	307	307	—	—	—	—
58	353cerega	307	52	—	153	—	102
60	Marcin_smu	301	265	—	—	—	36
61	receed	300	102	198	—	—	—
62	hank55663	298	—	—	—	63	235
63	Froggygua	291	—	—	—	—	291
64	fanache99	288	—	131	—	105	52
65	Isonan	281	107	157	—	—	17
66	dario2994	280	94	128	—	58	—
67	KostasKostil	277	—	—	277	—	—
68	jiangly_fan	273	—	—	157	116	—
69	Rafbill	272	80	—	—	87	105
70	ugly2333	266	—	138	54	—	74
71	fivedemands	265	—	—	—	265	—
72	Temotoloraia	257	—	—	226	10	21
73	Elegia	254	—	254	—	—	—
74	heno239	246	—	176	70	—	—
75	Egor	244	—	—	244	—	—
75	AliShahali1382	244	85	24	135	—	—
77	l1ll5	238	34	—	—	—	204
78	kotamanegi	235	—	—	235	—	—
78	_h_	235	—	235	—	—	—
80	dorijanlendvaj	228	10	—	52	166	—
81	noimi	225	—	94	34	97	—
82	TLEwpdus	213	—	2	211	—	—
83	ehnryx	211	—	211	—	—	—
84	WangZhikun	204	—	204	—	—	—
84	renascencepjw0510	204	—	—	204	—	—
86	fastmath	202	92	110	—	—	—
86	amethyst0	202	181	—	21	—	—
88	inaFSTream	198	—	—	—	—	198
89	atomicenergy	197	46	16	—	—	135
90	uwi	192	192	—	—	—	—
90	gs18115	192	—	—	—	—	192
90	slime	192	—	—	—	192	—
93	Geothermal	188	—	—	—	157	31
94	Argentina	186	—	—	—	186	—
94	nantf	186	—	186	—	—	—
94	YeongTree	186	186	—	—	—	—
97	voidmax	181	—	—	—	181	—
97	scott_wu	181	—	—	181	—	—
99	Torta	177	—	—	80	—	97
100	nick452	176	—	—	—	176	—
101	fedoseev.timofey	174	39	63	72	—	—
102	ccf_n0i	171	—	—	—	171	—
102	MAOooOAM	171	171	—	—	—	—
104	_--_-__-	166	166	—	—	—	—
105	kmjp	165	—	—	22	27	116
106	Nachia	164	138	—	26	—	—
107	Anadi	161	161	—	—	—	—
107	huhaoo	161	—	—	—	161	—
109	Ra16bit	158	66	—	—	92	—
110	dsgrekova2	157	157	—	—	—	—
110	peti1234	157	—	125	—	32	—
110	zh0ukangyang	157	—	—	—	—	157
113	tute7627	155	—	27	58	—	70
114	AutumnKite	153	—	—	—	—	153
115	Egor.Lifar	152	—	8	16	128	—
116	isaf27	150	63	—	87	—	—
117	Swistakk	149	—	—	149	—	—
117	TLE	149	—	—	—	149	—
119	Amoo_Safar	145	—	—	145	—	—
119	__fishingprince__	145	—	—	—	—	145
119	mnaeraxr	145	145	—	—	—	—
119	137_345_2814	145	—	—	—	145	—
123	saba2000	144	125	—	19	—	—
124	ppavic	142	142	—	—	—	—
125	m_99	141	22	—	—	119	—
126	Xellos	140	—	92	—	48	—
127	mtsd	138	—	—	—	—	138
127	wuwuwu	138	—	—	—	138	—
129	crackersamdjam	135	—	—	—	135	—
129	conqueror_of_tourist	135	50	37	—	—	48
131	flashmt	131	—	—	94	—	37
131	syvjjp416	131	—	—	131	—	—
133	qwerty787788	128	—	—	128	—	—
133	Zhtluo	128	—	—	—	—	128
135	Noam13	126	2	—	2	122	—
136	Melania	125	—	—	—	—	125
136	abc864197532	125	—	—	125	—	—
138	AlesyaIvanova	124	—	74	—	50	—
139	Arayi	122	122	—	—	—	—
139	Hazyknight	122	—	122	—	—	—
139	djq_cpp	122	—	—	—	—	122
142	errorgorn	121	—	—	43	—	78
143	krijgertje	119	—	119	—	—	—
143	ainta	119	—	—	—	—	119
145	potato167	117	—	—	37	22	58
146	eatmore	116	116	—	—	—	—
146	Merkurev	116	—	—	—	116	—
148	simonlindholm	113	—	—	113	—	—
148	Alan233	113	—	—	—	—	113
148	Yongaron	113	—	113	—	—	—
148	chenyanbo	113	113	—	—	—	—
152	Karry5307_AK_NOI2022	110	—	—	—	—	110
153	Pyqe	108	—	45	—	63	—
154	Itst_boyfriend	107	—	—	107	—	—
154	Tiramister	107	—	107	—	—	—
154	asdsasd	107	—	—	—	107	—
157	Wu_Ren	105	105	—	—	—	—
157	ix35	105	—	105	—	—	—
159	Alex_2oo8	102	—	—	102	—	—
160	antontrygubO_o	99	—	99	—	—	—
160	krismaz	99	—	—	99	—	—
160	tabr	99	—	—	—	99	—
160	Comet_Honeymoon	99	99	—	—	—	—
164	oleh1421	98	—	4	—	94	—
165	donentseto	97	97	—	—	—	—
165	Suika_predator	97	—	97	—	—	—
167	BurnedChicken	96	—	—	60	29	7
168	dengyaotriangle	94	—	—	—	—	94
169	Kodaman	92	—	—	92	—	—
170	LiciaDu	90	—	—	90	—	—
170	ljcleo	90	—	—	—	—	90
170	TeaPot	90	76	—	14	—	—
173	Aishiteru.	87	87	—	—	—	—
173	Enchom	87	—	87	—	—	—
173	antekb	87	—	—	—	—	87
176	God_Of_Blunder	85	—	—	—	85	—
176	voover	85	—	—	85	—	—
176	sumitacchan	85	—	85	—	—	—
176	Skyqwq	85	—	—	—	—	85
180	szhlg	83	83	—	—	—	—
180	skywalkert	83	—	—	83	—	—
180	emptyhope	83	—	—	—	—	83
180	ezLadder	83	—	—	—	83	—
184	djq_fpc	80	—	80	—	—	—
184	Roundgod	80	—	—	—	—	80
186	SirShokoladina	78	78	—	—	—	—
186	scli_weapon	78	—	—	78	—	—
188	C.S.T.T	76	—	—	—	76	—
188	AoLiGei	76	—	—	—	76	—
188	orzdevinwang	76	—	76	—	—	—
188	dXqwq	76	—	—	—	—	76
192	prick	74	74	—	—	—	—
192	IntoTheNight	74	—	17	56	—	1
194	szb	72	72	—	—	—	—
194	KevinWan	72	—	—	—	—	72
196	zscoder	71	37	—	—	34	—
197	hamlet	70	70	—	—	—	—
197	timmyfeng	70	—	70	—	—	—
199	happyguy656	68	—	—	—	—	68
199	veckoper	68	—	68	—	—	—
199	Izumi_Chiaki	68	—	—	—	68	—
202	ynsm	66	—	66	—	—	—
202	awoo	66	—	—	—	66	—
202	K_T_O	66	—	—	—	—	66
205	Rubikun	63	—	39	—	—	24
205	Kalptaru	63	—	—	—	—	63
207	jonathanirvings	62	—	—	—	—	62
207	jcvb	62	62	—	—	—	—
207	izone	62	—	62	—	—	—
210	20I6wudi	60	—	—	—	—	60
210	AlexLuchianov	60	—	60	—	—	—
210	saketh	60	60	—	—	—	—
213	risujiroh	58	58	—	—	—	—
213	Monogon	58	—	58	—	—	—
213	peltorator	58	58	—	—	—	—
216	SolarPea	56	—	—	—	—	56
216	tfg	56	—	—	—	56	—
216	Quirrel	56	—	56	—	—	—
219	Pa.Nic	54	—	54	—	—	—
219	NeoOrgano	54	—	—	—	54	—
221	alireza_kaviani	52	—	—	—	52	—
222	s_r_f	50	—	50	—	—	—
222	icypiggy	50	—	—	—	—	50
224	_Ash__	48	—	48	—	—	—
224	Shibuyap	48	48	—	—	—	—
226	mshcherba	46	—	46	—	—	—
226	Barichek	46	—	—	—	46	—
226	yspm	46	—	—	—	—	46
226	PuRpLe_FoReVeR	46	46	—	—	—	—
230	wifiiii	45	—	—	—	45	—
230	Gary	45	—	—	—	45	—
230	LMOliver	45	—	—	—	—	45
233	zhangzy	43	—	43	—	—	—
233	xuanyi	43	43	—	—	—	—
233	arvindf232	43	—	—	—	—	43
236	lucaperju	41	—	—	—	41	—
236	jiangIy	41	—	—	41	—	—
236	Vercingetorix	41	—	—	—	—	41
236	doped.silicon	41	41	—	—	—	—
236	shennong	41	—	—	—	41	—
241	shb	39	—	—	—	—	39
241	Maripium	39	—	—	39	—	—
243	cheissmart	37	—	—	—	37	—
243	stevenkplus	37	—	—	37	—	—
245	leaf1415	36	—	36	—	—	—
245	AnandOza	36	36	—	—	—	—
245	klimoza	36	—	—	—	36	—
248	Iscream2001	34	—	34	—	—	—
249	Bellalabella	32	32	—	—	—	—
249	olmrgcsi	32	—	—	32	—	—
249	soltanbh	32	—	32	—	—	—
249	Sung.An	32	—	—	—	—	32
253	EndSinger	31	—	—	—	31	—
253	ildth	31	—	31	—	—	—
253	FluffyT	31	31	—	—	—	—
256	Nyaan	29	—	—	29	—	—
256	amnesiac_dusk	29	29	—	—	—	—
256	Marckess	29	—	29	—	—	—
259	dragonslayerintraining	27	27	—	—	—	—
259	Nebuchadnezzar	27	—	—	—	—	27
261	wasa855	26	—	—	—	26	—
261	catupper	26	26	—	—	—	—
261	Tlatoani	26	—	26	—	—	—
261	MofK	26	—	—	—	—	26
265	KeNaj712	24	—	—	24	—	—
265	ALILILILILI-KHAN	24	—	—	—	24	—
265	Zayin	24	24	—	—	—	—
268	_menhera	22	—	22	—	—	—
268	16silver	22	—	—	—	—	22
270	sava-cska	21	21	—	—	—	—
270	sd0061	21	—	21	—	—	—
270	yuto1115	21	—	—	—	21	—
273	w0nsh	19	19	—	—	—	—
273	rniya	19	—	—	—	19	—
273	S2speed	19	—	—	—	—	19
273	almogwald	19	—	19	—	—	—
277	yosupo	18	—	—	4	—	14
278	HoshimiOWO	17	17	—	—	—	—
278	xay5421	17	—	—	—	17	—
280	C137	16	16	—	—	—	—
280	VladProg	16	—	—	—	16	—
282	Nero	14	—	14	—	—	—
282	sugarrr	14	—	—	14	—	—
282	dendi239	14	14	—	—	—	—
282	cuom1999	14	—	—	—	14	—
286	olphe	13	—	—	—	13	—
286	SW2000	13	13	—	—	—	—
286	PaiGuGou	13	—	—	—	—	13
286	yyljkydr	13	—	13	—	—	—
290	Akulyat	12	—	—	7	5	—
291	Yukikaze_	11	—	11	—	—	—
291	wiwitrifai	11	11	—	—	—	—
291	JeanBombeur	11	—	—	—	11	—
291	Atreus	11	—	—	11	—	—
295	Obsidian	10	—	—	10	—	—
295	Laurie	10	—	—	—	—	10
295	al3xstr33t	10	—	10	—	—	—
298	Ali.Kh	8	—	—	8	—	—
298	nweeks	8	—	—	—	8	—
298	Kostroma	8	—	—	—	—	8
298	magga	8	8	—	—	—	—
302	Nots0fast	7	—	—	—	7	—
302	zyb	7	—	7	—	—	—
302	EnAnimant	7	7	—	—	—	—
305	NoLongerRed	5	—	—	5	—	—
305	kamer	5	—	—	—	—	5
305	craborac	5	5	—	—	—	—
308	TheScrasse	4	—	—	—	—	4
308	tin-jyu	4	4	—	—	—	—
308	strongerthanspeed	4	—	—	—	4	—
311	iaNTU	3	—	—	1	—	2
312	dfcmd	2	—	—	—	2	—
313	Jlytxdy	1	1	—	—	—	—
313	GRT_2018	1	—	—	—	1	—

codeforces global rounds, xtx, globals, globals 2021

+124

MikeMirzayanov
5 months ago
2

C++20 Is Released

By MikeMirzayanov, 7 months ago, In English

Hello, Codeforces.

Please, welcome c++20 support on Codeforces. Yes, it is 64-bit. Thanks to Brecht Sanders: I used his distribution GCC-11.2.0-64 from https://winlibs.com/.

If you have installed PBOX, you can add this compiler with the line pbox install gcc11-64-winlibs. Probably, a good idea is to add C:\Programs\gcc11-64-winlibs\bin into the PATH. More about PBOX you can read here.

I use the compilation command line similar to other GCC installations: g++ -Wall -Wextra -Wconversion -static -DONLINE_JUDGE -Wl,--stack=268435456 -O2 -std=c++20 <source>. The only differences are -std=c++20 and -Wall -Wextra -Wconversion (I plan to use somehow such warnings in Polygon to suggest fixes in uploaded files).

Now you can use c++20 in your solutions. I'm not sure there are many features useful in competitive programming. Probably, I'm wrong. For example, now you can write vector v{vector{1, 2}}; instead of vector<vector<int>> v{vector<int>{1, 2}};. What else is useful? Please, if you are good with modern C++ then write.

You might be interested in looking at such a table. Before implementation, I always test every C++ distribution for the efficiency of reading and writing large amounts of data. For example, the latest GCC compiler from MSYS2 is terribly slow in some cases. I don't want to use it here. Also, it happens that some specifiers like lld or Lf work unexpectedly. In the table by reference, the second line is the added compiler. The columns correspond to different tests. The cell contains the time of the test execution. If I have time, I will someday publish scripts for testing c++ compiler installations.

Bye for now,
— Mike

codeforces, c++, gcc11, c++20

+1524

MikeMirzayanov
7 months ago
86

PyPy 3-64 Is Released

By MikeMirzayanov, 7 months ago, In English

Hey! I'm happy to report that Pypy3 is supported. Please test that it works as expected. Thanks!

P.S. I remember about GCC 11, it is in the progress. See you soon.

codeforces, pypy, pypy3, pypy3-64

+361

MikeMirzayanov
7 months ago
16

Codeforces Round #743 Is Unrated: Investigating the Reason

By MikeMirzayanov, 8 months ago, In English

Hello.

Sorry for it. Actually, right now I don't have any idea why testing is so slow now. Obviously, it doesn't work as expected. It is not because of problems. So please don't blame writers or coordinators. I'm investigating the reason, but don't see it now.

I myself am very upset and I apologize to the authors, coordinator, and participants. I will do my best to find the cause and fix it. Surprisingly, we haven't made any big changes to this part of the system lately. But something went wrong.

Mike.

UPD: https://codeforces.com/blog/entry/95081#comment-841873

codeforces

+1522

MikeMirzayanov
8 months ago
141

Discussion: Modern G++ Command Line

By MikeMirzayanov, 8 months ago, In English

Hello Codeforces!

I am in the process of making improvements and updates to the judgment machines. I've read the post https://codeforces.com/blog/entry/94587 and I think, maybe it is a good idea to make such a compilation line -O3 -funroll-loops -march=native -mtune=native? I haven't done any research that it is definitely better than -O2 and it is best in the general case for CP solutions. In a way, this will only strengthen the gap from Python/PyPy/Java, on the other hand: in pragmas and so you can set up everything. What do you think? What are suggestions to the command line?

P.S. You got it right. Yes, gcc11 std=c++20, pypy3 64-bit and more are coming.

cpp, g++, gcc, clang

+830

MikeMirzayanov
8 months ago
83

Maintenance works on Round 739. Don't be surprised.

By MikeMirzayanov, 9 months ago, In English

Hello, Codeforces.

We want to run a series of load testing in the production environment for running contests. For this reason, Codeforces Round 739 will be temporarily extended (in order to test it at the current round). We will temporarily disable the ability to send solutions to it so that its extended duration will not affect the results. After the completion of the work, the duration of the round will be returned.

Our current plan is to finish today.

Mike

codeforces, maintenance

+225

MikeMirzayanov
9 months ago
42

Google Code Jam 2021: Round 2

By MikeMirzayanov, 12 months ago, In English

Hey!

As I don't see the post discussing the round, I decided to write this.

I do not participate much in contests now. But I love Code Jam. Thanks to problem writers and organizers!

It seemed to me that this round was no more difficult than the previous one. How do you like it?

I liked the problems:

A (tags: interactive, constructive): strange problem — the most naive approach fits into the requirements on the total cost of requests;
B (tags: number theory, dp): I wrote some kind of DP with memorization of $$$(a, s)$$$, where $$$a$$$ is the last element in the sequence we already placed (I build in increasing order) and $$$s$$$ is the total sum for the future elements. I don't have a proof why it works fast, probably because of the number of divisors is small.
C (tags: combinatorics, recurrence): the last occurrence of 1 is the position of $$$n$$$, so we can divide sequence with this position on two parts and use DP to calculate the answer (don't forget to multiply on binomial coefficient);
D (tags: graphs, flows, greedy): I used min-cost-flow to match Ms on the first field and the second in optimal way. I tried all possible values of flow to iterate over all possible pairs of Ms I want to match and took best cost among all choices.

codejam, 2021

+659

MikeMirzayanov
12 months ago
63

Codeforces: Results of 2020 [Annual Report]

By MikeMirzayanov, 13 months ago, In English

Hi Codeforces!

Yes, I know it's already April. Time flies so fast lately! Exactly a year ago we were just learning all the "delights" of lockdown.

So let's remember this 2020! What was it like? I don't know about you, but we had a hell of a lot of work.

I will now show you some graphs and you will be very surprised. Lockdown effect? Of course, but we did our best too.

Many thanks to everyone who did not stand aside! In 2020, we celebrated our 10th anniversary and crowdfunding money helps us grow and move forward. You helped us and each other. Thank you. Thank you for your contribution!

We've been working hard all year to make this community a better place. Did it work out? It's up to you to judge. Many thanks to everyone who invested time and effort:

geranazavr555, kuviman, cannor147 helped a lot with development and new features;
Una_Shem provided great organizational assistance;
our problem coordinators are the greatest: KAN, antontrygubO_o, isaf27, 300iq, significant assistance was provided by BledDest, adedalic and Nebuchadnezzar, vovuh for preparing Div3 rounds;
stingray advised and helped set up the network;
our friends from VK for their help in our infrastructure;
and help of problem writers and testers is immortal!

Time to take stock of 2020.

Partner Events

We are pleased to hold programming competitions with companies or for companies. I'm sure this is a great way to support the community of young programmers and hire talented candidates. Here is a list of our main partners this year:

Telegram and personally Pavel Durov is supporting Codeforces activities for many years, every regular round is held with their help, thank you!
ICPC — in 2020 we held several joint events (and we liked it!), I hope there will be more
Mail.Ru — Technocup and Russian AI Cup
VK, VK Cup — now a personal multi-track competition for Russian-speaking programmers
XTX Markets, Codeforces Global Rounds — a series of 6 rounds with a separate scoring and souvenirs for the best participants
Harbour.Space University — a series of educational rounds, the selection of summer school Tech Scouts
JetBrains, Kotlin Heroes Rounds — Kotlin programming language contests
Huawei — research competitions (marathons) with elements of machine learning
Raiffeisenbank — round for both divisions with cool prizes
Grakn Labs — round for both divisions with money prizes
Microsoft, Microsoft Q # Coding Contest — unusual quantum computing competition

2020, codeforces, report

+612

MikeMirzayanov
13 months ago
31

Codeforces: Results of 2020 [list some changes and improvements]

By MikeMirzayanov, 14 months ago, In English

Hello, Codeforces!

I understand that 2021 has been going on for a long time, but here I have picked up a subset of some of the improvements that the Codeforces team made in 2020. Soon I will publish numbers (no, charts) with statistics for 2020. In the meantime, I bring to your attention a list of changes and improvements.

By the way, this is a decent list. This is about half to a quarter of all changes. It's just that other changes are more often somewhere in the internals of the system and are not visible to users. Please read this list. Each item is the effort of someone from the team. Thanks to geranazavr555, kuviman and cannor147 for their efforts. You've made our platform better! Well, by the way, I don't quit programming and many improvements were made by me.

The items on the list are written in a concise and informal form, many of the items I just copied from commit messages from git. If you want more details — ask in the comments, we will tell you! Of course, I forgot to include some improvements in the list.

codeforces, 2020, results

+1394

MikeMirzayanov
14 months ago
65

Goodbye 2020. Hello 2021!

By MikeMirzayanov, 16 months ago, In English

Hello Codeforces!

This unusual and difficult 2020 has come to an end! What will the new year be like? I wish all of us that we have the opportunity to meet in person so that the contests take place not only online. I ask you to think of something important and good. Let this wish come true!

We have had a large number of rounds this year. I hope we have pleased you with interesting problems. Thanks to the round coordinators and writers! You make our community richer. Please make us happy in 2021!

I wish the participants victories over yourself (and over problems!) and development of your skills, interest and curiosity!

Hello, 2021!

And we have traditional gifts!

Change Handle Feature

Again, this year if you took part in at least 10 rounds you can request a handle of an inactive participant. It means that the participant should have a period of activity on Codeforces of at most 180 days, this period should be in 2017 or earlier. The inactive participant can't have posted comments, messages and so on. It can't take part in more than 2 contests. It will be automatically renamed and informed by email. A user has the opportunity to request back his/her handle: in this case, we will roll back the change and return your previous handle to you. If you can't change your handle to another, it means that some requirement doesn't meet. Please do not ask me to do something with it. Especially, I do not like requests like "this is my second account, I took an interesting handle myself". I'm not Santa Claus.

Talking about handles I always
reminisce the following story. Once a user wrote me the message: "Please change my handle from I_love_Valya to I_love_Sveta, as I no longer love Valya ..."

New Year's Masquerade of Colors and Ranks

The traditional magical tab has appeared in the profile setting. Happy New Year!

— MikeMirzayanov

2021, happy new year

+2135

MikeMirzayanov
16 months ago
244

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