Problem A
Datum — Problem Statistics

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Submissions	10483
Accepted submissions	6113
Submission ratio	58.31%
Authors	5920
Full solves [?]	5682
Full solve Ratio	95.98%

#	User	Runtime	Language	Date
1	Thomas Feld	0.01 s	Bash	2023-04-25 08:59:28
2	Chenzhang Hu	0.01 s	Bash	2023-09-25 17:50:34
3	Will Killian	0.01 s	Bash	2024-04-19 20:55:36
4	Russell Ng	0.01 s	Bash	2025-08-05 19:29:20

#	User	Runtime	Language	Date
1	Pontus Eriksson	0.01 s	C#	2017-04-27 17:46:45
2	Madelyn Reyes	0.01 s	C#	2017-06-03 21:27:29
3	Faisal Rahman	0.01 s	C#	2017-10-31 02:55:35
4	Ziga Staresinic	0.01 s	C#	2017-12-25 16:06:23
5	John Ladera	0.01 s	C#	2018-03-19 05:09:18
6	Klas af Geijerstam	0.02 s	C#	2017-04-11 15:17:05
7	Duelene Olson	0.02 s	C#	2017-04-20 22:41:45
8	Rasmus Brants	0.02 s	C#	2017-04-26 15:32:51
9	Jakub Jagiello	0.02 s	C#	2017-05-09 10:43:53
10	Mauricio Viscarra	0.02 s	C#	2017-05-27 06:44:00

#	User	Runtime	Language	Date
1	Dmytro Bihniak	0.01 s	Common Lisp	2019-08-26 12:45:59
2	John Dandy	0.01 s	Common Lisp	2020-01-25 23:21:52
3	wibi	0.01 s	Common Lisp	2020-08-16 23:52:47
4	David Cawthon	0.02 s	Common Lisp	2019-04-25 01:45:56

#	User	Runtime	Language	Date
1	Emil Jessen	0.04 s	F#	2020-09-24 20:08:44
2	Jacob Harris Cryer Kragh	0.04 s	F#	2022-05-30 20:16:55
3	David Vinje	0.05 s	F#	2022-08-02 18:27:43
4	Elias Illeris Poggi	0.06 s	F#	2025-02-26 17:20:03

#	User	Runtime	Language	Date
1	Ben Hutchinson	0.00 s	Go	2023-10-16 10:46:24
2	Vadim Popolitov	0.00 s	Go	2025-06-02 12:46:26
3	Jimmy Nejtron	0.02 s	Go	2022-12-22 15:54:29
4	Hidden user	0.02 s	Go	2023-01-21 03:14:55
5	Ross O'Sullivan	0.07 s	Go	2018-08-17 16:35:51
6	Alejandro Germain	0.07 s	Go	2018-10-03 19:44:32
7	Eric Martin	0.07 s	Go	2018-12-27 07:32:18
8	Krzysztof Gibuła	0.07 s	Go	2019-01-06 15:24:19
9	Erik Pettersson	0.07 s	Go	2019-04-11 16:19:57
10	Hidden user	0.07 s	Go	2021-12-15 14:09:42

#	User	Runtime	Language	Date
1	Nathaniel Lahn	0.04 s	Java	2025-02-25 03:46:38
2	William Brigham	0.05 s	Java	2017-04-19 03:57:15
3	Pontus Eriksson	0.05 s	Java	2017-04-25 21:49:08
4	Martijn Muijsers	0.05 s	Java	2017-04-28 10:18:40
5	Samuel Klingström	0.05 s	Java	2017-04-29 19:40:04
6	James Black	0.05 s	Java	2017-05-02 02:13:03
7	Rick van Rheenen	0.05 s	Java	2017-05-18 16:37:41
8	Finn Lidbetter	0.05 s	Java	2017-05-18 19:30:59
9	Liam Keliher	0.05 s	Java	2017-06-01 08:04:21
10	Mike Beckers	0.05 s	Java	2017-06-13 13:59:39

#	User	Runtime	Language	Date
1	Hidden user	0.04 s	JavaScript (Node.js)	2024-07-12 05:13:50
2	Ismail Tahiri	0.05 s	JavaScript (Node.js)	2018-07-11 16:23:44
3	Christoffer Karlsson	0.05 s	JavaScript (Node.js)	2018-07-21 15:41:38
4	Carl Sundvall	0.05 s	JavaScript (Node.js)	2018-10-26 10:40:47
5	Dario Delle Donne	0.05 s	JavaScript (Node.js)	2018-12-17 21:47:26
6	Tomáš Necky Necuda	0.05 s	JavaScript (Node.js)	2019-02-05 21:43:22
7	Gurpartap Singh Bhatti	0.05 s	JavaScript (Node.js)	2019-02-16 04:48:06
8	José Lucas	0.05 s	JavaScript (Node.js)	2019-03-06 18:03:52
9	Sander Hellesø	0.05 s	JavaScript (Node.js)	2019-04-14 03:55:31
10	Hidden user	0.05 s	JavaScript (Node.js)	2019-05-30 17:06:10

#	User	Runtime	Language	Date
1	Bjørn Chr. Soltvedt	0.01 s	JavaScript (SpiderMonkey)	2017-04-10 10:39:20
2	Peter Kedemo	0.01 s	JavaScript (SpiderMonkey)	2017-06-04 18:11:30
3	Spencer Smith	0.01 s	JavaScript (SpiderMonkey)	2017-06-06 17:28:55
4	Michael Hjortholt	0.01 s	JavaScript (SpiderMonkey)	2017-07-11 00:25:15
5	Davíð Helgason	0.01 s	JavaScript (SpiderMonkey)	2017-08-07 19:01:22
6	Peter Menyes	0.01 s	JavaScript (SpiderMonkey)	2017-08-08 22:36:19
7	Aletta Géczi	0.01 s	JavaScript (SpiderMonkey)	2017-09-03 12:44:09
8	Martin Jay	0.01 s	JavaScript (SpiderMonkey)	2017-10-31 16:11:22
9	Nicklas Utgaard	0.01 s	JavaScript (SpiderMonkey)	2017-12-03 14:04:37
10	Manish Paudel	0.01 s	JavaScript (SpiderMonkey)	2018-03-09 05:25:12

#	User	Runtime	Language	Date
1	Danny Robinson	0.50 s	Julia	2023-09-01 06:00:45
2	Timothy Gaede	0.53 s	Julia	2024-03-19 11:14:43

#	User	Runtime	Language	Date
1	Vyas Nellutla	0.15 s	Kotlin	2018-10-03 04:19:36
2	Jacob Huebner	0.16 s	Kotlin	2020-03-17 22:12:31
3	Neil Harmon	0.19 s	Kotlin	2019-04-02 11:01:50
4	MisterDerpie	0.19 s	Kotlin	2021-07-02 21:02:48
5	Troy Warmboe	0.21 s	Kotlin	2018-10-20 06:45:43
6	Clinton Walker	0.21 s	Kotlin	2019-09-09 08:11:13
7	Jonathan Soo	0.21 s	Kotlin	2019-10-21 10:44:40
8	Jörgen Andersson	0.21 s	Kotlin	2020-06-29 21:09:59
9	Adam Rankin	0.21 s	Kotlin	2023-05-01 06:15:40
10	Jesper Bech Christensen	0.21 s	Kotlin	2023-09-29 14:04:32

#	User	Runtime	Language	Date
1	Fredrik Eriksson	0.00 s	OCaml	2024-10-17 21:51:40

#	User	Runtime	Language	Date
1	Hidden user	0.00 s	Odin	2025-04-24 21:10:30

#	User	Runtime	Language	Date
1	David Connolly	0.00 s	Pascal	2017-09-04 15:37:49
2	Vova Podkorytov	0.00 s	Pascal	2018-01-03 10:20:16
3	Egor Shchetinin	0.00 s	Pascal	2018-01-15 14:59:21
4	Ingemar Ragnemalm	0.00 s	Pascal	2018-03-01 14:10:05
5	Jiyeon	0.00 s	Pascal	2019-04-12 15:40:24
6	Chan Hok To	0.00 s	Pascal	2020-02-11 13:30:57
7	Huỳnh Minh Lâm	0.00 s	Pascal	2022-09-27 15:54:51

#	User	Runtime	Language	Date
1	Peter Sofronas	0.01 s	PHP	2017-07-13 21:24:59
2	Helbin Grégory	0.01 s	PHP	2020-01-20 13:07:27
3	Renate Fiala-Lundström	0.01 s	PHP	2021-04-15 16:49:11
4	Muhammad Asyraf bin Akop	0.01 s	PHP	2022-05-13 05:05:46
5	Susanne Ragnemalm	0.01 s	PHP	2024-05-12 13:23:14

#	User	Runtime	Language	Date
1	Andriy Zyevakov	0.01 s	Prolog	2017-06-16 20:19:36
2	Hadi Qovaizi	0.01 s	Prolog	2018-06-28 23:57:44
3	Hakan Kjellerstrand	0.02 s	Prolog	2023-01-21 10:58:54

#	User	Runtime	Language	Date
1	Christofer Ohlsson	0.02 s	Python 2	2017-04-06 20:27:55
2	Meher Béjaoui	0.02 s	Python 2	2017-06-01 23:04:45
3	Johan Wind	0.02 s	Python 2	2017-06-04 00:40:15
4	Jeff Robertson	0.02 s	Python 2	2017-08-09 21:10:46
5	Eoin Davey	0.02 s	Python 2	2017-09-08 21:44:27
6	Alex Meed	0.02 s	Python 2	2017-10-28 01:05:32
7	Andrei Stoica	0.02 s	Python 2	2017-11-06 17:05:25
8	Rio Harapan Pangihutan	0.02 s	Python 2	2017-11-17 04:45:02
9	Sigurður Jens Albertsson	0.02 s	Python 2	2017-11-20 22:52:49
10	shrek the ogre lord	0.02 s	Python 2	2017-12-03 07:05:00

#	User	Runtime	Language	Date
1	Robert Welin-Berger	0.02 s	Python 3	2017-04-06 20:01:52
2	Bernhard Kartefla	0.02 s	Python 3	2017-04-07 13:03:09
3	Sebastian Dolan	0.02 s	Python 3	2017-04-07 19:03:37
4	Wayne	0.02 s	Python 3	2017-04-07 20:08:39
5	Ciara Godwin	0.02 s	Python 3	2017-04-08 00:45:23
6	Anthony Clays	0.02 s	Python 3	2017-04-17 12:07:21
7	James Hamm	0.02 s	Python 3	2017-04-25 03:27:53
8	Денис Соболев	0.02 s	Python 3	2017-04-25 11:55:49
9	Joshua Guerin	0.02 s	Python 3	2017-04-26 23:17:56
10	Martin Jackson	0.02 s	Python 3	2017-05-01 19:50:11

#	User	Runtime	Language	Date
1	Hidden user	0.03 s	Ruby	2017-05-07 23:11:33
2	Clifford Owino	0.03 s	Ruby	2017-05-25 06:39:08
3	Mona Dadoun	0.03 s	Ruby	2017-12-30 18:57:57
4	Paul Vinell	0.03 s	Ruby	2018-03-13 13:42:21
5	Omar Al-Khashab	0.04 s	Ruby	2018-04-23 10:20:10
6	Joel Niemelä	0.04 s	Ruby	2018-05-02 05:57:11
7	Jason Cheong-Kee-You	0.04 s	Ruby	2018-05-27 02:48:38
8	Daniel Harder	0.04 s	Ruby	2018-09-01 00:25:28
9	Angelo Ruperti	0.04 s	Ruby	2019-08-14 16:29:50
10	Macdara mac an tSionnaigh	0.04 s	Ruby	2019-09-18 01:57:32

#	User	Runtime	Language	Date
1	Danial Haseeb	0.00 s	Swift	2023-10-09 18:26:23

#	User	Length	Language	Date
1	Russell Ng	28	Bash	2025-08-05 19:29:20
2	Chenzhang Hu	28	Bash	2025-09-12 16:28:11
3	Thomas Feld	29	Bash	2023-09-28 10:06:20
4	Will Killian	30	Bash	2024-04-19 20:59:17

#	User	Length	Language	Date
1	Martin Blom	186	C	2023-09-24 14:46:14
2	Mihir Patel	303	C	2018-01-15 15:51:31
3	Bokor	303	C	2018-05-11 16:07:54
4	Johan Öhlin	318	C	2017-07-03 11:17:47
5	winnie the pooh	320	C	2021-05-29 09:35:41
6	jadrs02	329	C	2020-12-18 12:42:32
7	Jovan Reynardo	340	C	2018-10-19 10:01:28
8	Hidden user	349	C	2019-04-24 10:02:28
9	Romario Putra	358	C	2019-10-20 17:50:17
10	Nguyễn Tiến Đạt	362	C	2019-04-24 14:32:07

#	User	Length	Language	Date
1	Mikael Palokangas	150	C#	2023-01-18 10:56:32
2	Jakub Jagiello	216	C#	2017-05-09 10:43:53
3	李陆屿	233	C#	2018-12-23 11:49:03
4	Klas af Geijerstam	244	C#	2017-04-11 15:17:05
5	Pierre Hébert	264	C#	2017-12-15 18:29:30
6	Lukas Brolin	264	C#	2022-04-04 17:18:07
7	Peter Nordh	274	C#	2018-06-09 22:27:42
8	Stoffe Malmberg	280	C#	2022-12-27 10:52:29
9	Steve Jia	281	C#	2018-08-21 15:32:31
10	Kunwei Zhang	287	C#	2018-02-04 04:28:45

#	User	Length	Language	Date
1	Patrick Jacobs	251	C++	2019-04-02 03:46:59
2	Admasu Abera	251	C++	2019-12-01 20:16:01
3	Richard Putra	253	C++	2018-02-19 05:42:07
4	apd	259	C++	2024-11-08 07:46:45
5	Timotius Jason	267	C++	2021-05-01 18:21:26
6	Basil Semuonov	269	C++	2019-11-27 12:25:50
7	Ritchie Goldwin	277	C++	2018-12-29 15:11:20
8	Ricky Chen	286	C++	2020-05-12 04:47:36
9	Grae Yeandle	289	C++	2017-04-29 17:26:12
10	Jan Livens	291	C++	2017-09-15 14:33:24

#	User	Length	Language	Date
1	John Dandy	293	Common Lisp	2020-01-25 23:21:52
2	David Cawthon	338	Common Lisp	2019-04-25 01:45:56
3	Dmytro Bihniak	372	Common Lisp	2019-08-26 12:45:59
4	wibi	427	Common Lisp	2020-08-16 23:52:47

#	User	Length	Language	Date
1	Jacob Harris Cryer Kragh	167	F#	2022-05-30 20:16:55
2	Emil Jessen	684	F#	2020-09-24 20:08:44
3	Elias Illeris Poggi	745	F#	2025-02-26 17:20:03
4	David Vinje	1199	F#	2022-08-02 18:27:43

#	User	Length	Language	Date
1	Hidden user	199	Go	2021-12-15 14:09:42
2	Samsu Sempena	203	Go	2020-11-06 14:17:34
3	Hidden user	205	Go	2017-12-01 19:56:44
4	Jimmy Nejtron	205	Go	2022-12-22 15:54:29
5	Alejandro Germain	215	Go	2018-10-03 19:44:32
6	Vadim Popolitov	233	Go	2025-06-02 12:46:26
7	Erik Pettersson	240	Go	2019-04-11 16:19:57
8	Kok Dith	243	Go	2021-07-29 18:47:11
9	Ben Hutchinson	245	Go	2023-10-16 10:46:24
10	Andi Baso Annas	362	Go	2020-09-02 05:46:46

#	User	Length	Language	Date
1	John Doe	92	Haskell	2023-05-02 15:54:15
2	Alex Marion	178	Haskell	2024-07-06 05:10:35
3	Daniel Cabral	194	Haskell	2022-02-03 16:47:23
4	Patrick Bahr	289	Haskell	2018-11-24 13:47:06
5	Zach Tschetter	289	Haskell	2021-08-28 01:47:12
6	Llaurence Git	303	Haskell	2018-11-06 11:26:17
7	Tim Put	313	Haskell	2021-04-19 00:20:35
8	Isidro Matos Bellido	321	Haskell	2018-03-31 13:45:38
9	Brent Yorgey	338	Haskell	2017-10-01 17:05:37
10	Jordan McIntyre	344	Haskell	2020-05-18 01:14:34

#	User	Length	Language	Date
1	Chandradhar Gowtham	269	Java	2019-02-28 17:00:07
2	Bryan Wong Wei Heng	310	Java	2019-11-06 12:25:14
3	Bhavpreet Singh Arneja	324	Java	2023-11-07 04:39:36
4	MADHUMITHA K	325	Java	2025-05-02 15:32:21
5	Terry Morris	335	Java	2020-12-18 18:40:02
6	Sergey Jakobsen	348	Java	2020-12-27 16:53:25
7	Robert Slutsky	360	Java	2018-01-25 01:05:36
8	Ryno Botes	362	Java	2025-04-22 00:18:15
9	Raymond Arrington	375	Java	2024-06-17 04:13:34
10	Pranav Addepalli	383	Java	2020-02-10 03:55:50

#	User	Length	Language	Date
1	Vu Van Dung	291	JavaScript (Node.js)	2022-09-14 19:58:56
2	Karim Dridi	327	JavaScript (Node.js)	2022-01-14 15:45:00
3	Emil Larsson	358	JavaScript (Node.js)	2020-06-28 20:40:02
4	Christoffer Karlsson	372	JavaScript (Node.js)	2018-07-21 15:41:38
5	Tomáš Necky Necuda	375	JavaScript (Node.js)	2019-02-05 21:43:22
6	Antoine Bauri	387	JavaScript (Node.js)	2021-02-18 20:56:37
7	Philipp Hergenhahn	387	JavaScript (Node.js)	2025-01-08 15:15:58
8	Ismail Tahiri	439	JavaScript (Node.js)	2018-07-11 16:23:44
9	jai ram	447	JavaScript (Node.js)	2019-12-04 14:38:43
10	Gustav Junedahl	493	JavaScript (Node.js)	2019-11-07 21:44:09

#	User	Length	Language	Date
1	Christian Pilegaard Cederquist	124	JavaScript (SpiderMonkey)	2022-10-31 01:56:28
2	Evan Magill	165	JavaScript (SpiderMonkey)	2024-04-19 05:27:57
3	Bjørn Chr. Soltvedt	181	JavaScript (SpiderMonkey)	2017-04-10 10:39:20
4	Jimmy Gustafsson	222	JavaScript (SpiderMonkey)	2022-06-23 21:37:04
5	Dylan Mcdougall	225	JavaScript (SpiderMonkey)	2019-11-18 19:29:28
6	Bernard Perrin	229	JavaScript (SpiderMonkey)	2019-01-18 20:10:26
7	Nguyễn Mạnh Phúc	236	JavaScript (SpiderMonkey)	2018-07-13 08:23:52
8	Goran Sherko Jawdat	248	JavaScript (SpiderMonkey)	2018-04-25 09:45:13
9	Aletta Géczi	249	JavaScript (SpiderMonkey)	2017-09-03 12:44:09
10	Gabor Varga	259	JavaScript (SpiderMonkey)	2018-03-31 15:34:41

#	User	Length	Language	Date
1	Danny Robinson	159	Julia	2023-09-01 06:00:45
2	Timothy Gaede	515	Julia	2024-03-19 11:14:43

#	User	Length	Language	Date
1	Albert Pala	204	Kotlin	2021-05-27 13:24:38
2	Dmitry Shostak	235	Kotlin	2018-08-28 09:37:01
3	Hamdanil Rasyid	237	Kotlin	2025-03-31 03:51:46
4	Jesper Bech Christensen	260	Kotlin	2023-09-29 14:04:32
5	Stefan Kennedy	269	Kotlin	2017-12-04 19:22:52
6	axl	270	Kotlin	2019-08-05 09:22:21
7	Frangel Hernández Martinez	317	Kotlin	2018-04-25 05:46:27
8	Mark Mathis	332	Kotlin	2018-10-13 03:24:26
9	Alan Pramuk	410	Kotlin	2022-07-29 13:54:57
10	Hidden user	416	Kotlin	2020-03-09 23:37:39

#	User	Length	Language	Date
1	Fredrik Eriksson	628	OCaml	2024-10-17 21:51:40

#	User	Length	Language	Date
1	Hidden user	569	Odin	2025-04-24 21:10:30

#	User	Length	Language	Date
1	Jiyeon	418	Pascal	2019-04-12 15:40:24
2	Ingemar Ragnemalm	431	Pascal	2018-03-01 14:10:05
3	David Connolly	719	Pascal	2017-09-04 15:37:49
4	Egor Shchetinin	1330	Pascal	2018-01-15 14:59:21
5	Huỳnh Minh Lâm	1529	Pascal	2022-09-27 15:54:51
6	Vova Podkorytov	1622	Pascal	2018-01-03 10:20:16
7	Chan Hok To	5944	Pascal	2020-02-11 13:30:57

#	User	Length	Language	Date
1	Renate Fiala-Lundström	94	PHP	2021-04-15 16:49:11
2	Helbin Grégory	122	PHP	2020-01-20 13:07:27
3	Susanne Ragnemalm	155	PHP	2024-05-12 13:23:14
4	Muhammad Asyraf bin Akop	172	PHP	2022-05-13 05:05:46
5	Peter Sofronas	327	PHP	2017-07-13 21:24:59

#	User	Length	Language	Date
1	Andriy Zyevakov	236	Prolog	2017-06-16 20:19:36
2	Hakan Kjellerstrand	263	Prolog	2023-01-21 10:58:54
3	Hadi Qovaizi	1634	Prolog	2020-06-09 03:33:56

#	User	Length	Language	Date
1	Marc Lozier	112	Python 2	2019-07-28 19:42:11
2	Simon Vestin	115	Python 2	2019-01-17 12:31:30
3	Oscar Melin	115	Python 2	2019-07-23 20:04:15
4	Wendirad Demelash	120	Python 2	2019-03-14 16:23:49
5	Hidden user	120	Python 2	2019-11-24 01:36:51
6	Çağdaş Öztekin	123	Python 2	2017-08-29 06:20:29
7	Gustavo Ribeiro	124	Python 2	2018-09-22 02:56:14
8	Kuenzang Choden	125	Python 2	2019-05-09 20:43:29
9	Frederik Højholt	140	Python 2	2017-10-13 19:14:20
10	Johan Lyts	143	Python 2	2019-03-07 22:00:02

#	User	Length	Language	Date
1	Will Killian	85	Python 3	2024-04-19 18:39:49
2	Lawry Sorenson	86	Python 3	2023-01-13 00:54:03
3	Clement Oh	86	Python 3	2023-05-18 16:07:35
4	Tommi Järvenpää	88	Python 3	2024-03-19 07:43:23
5	Josh Taylor	89	Python 3	2022-09-30 17:41:34
6	Andre Josiah Budianto	92	Python 3	2023-01-03 08:01:06
7	Meng Siong Hwee	92	Python 3	2023-01-07 16:44:30
8	Adam Levav	92	Python 3	2023-01-19 00:13:46
9	Thomas Delapart	92	Python 3	2024-01-18 09:37:07
10	Clavianus Juneardo	95	Python 3	2018-06-21 20:01:05

#	User	Length	Language	Date
1	Thomas Feld	47	Ruby	2023-01-04 15:38:44
2	dick move	64	Ruby	2022-12-06 18:50:42
3	Abolfazl Gol	85	Ruby	2018-07-29 12:19:37
4	Régis Hanol	86	Ruby	2022-01-06 23:29:47
5	Olivia Bednar	97	Ruby	2021-11-05 06:34:09
6	Eugen Neagoe	101	Ruby	2023-05-05 15:42:36
7	John Ray Clementz A. Servo	101	Ruby	2025-08-06 13:29:56
8	Lim Ming Yean	102	Ruby	2018-11-14 08:03:58
9	Daniel Harder	104	Ruby	2018-09-01 00:25:28
10	Jason Cheong-Kee-You	109	Ruby	2018-05-27 02:48:38

#	User	Length	Language	Date
1	Vincent Lagerros	354	Rust	2025-01-17 10:21:27
2	Emil Dichmann	462	Rust	2025-09-21 12:55:47
3	Pankajkumar Patro	584	Rust	2024-07-18 21:41:31
4	Florent Haratyk	602	Rust	2019-03-30 20:26:54
5	Joe Blower	627	Rust	2025-06-06 03:35:44
6	Hovig Manjikian	668	Rust	2019-12-28 21:19:46
7	Andriy Semenistiy	722	Rust	2021-02-13 15:32:10
8	Peter Hrvola	724	Rust	2019-04-12 15:58:11
9	Phoxy Tr0ut	731	Rust	2025-08-11 01:00:37
10	Michael Vesterli	838	Rust	2019-04-12 16:36:03

#	User	Length	Language	Date
1	Danial Haseeb	613	Swift	2023-10-09 18:26:23

Solution running time distribution