Problem A
Magic Trick — Problem Statistics

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Submissions	9970
Accepted submissions	5697
Submission ratio	57.14%
Authors	5280
Full solves [?]	5039
Full solve Ratio	95.44%

#	User	Runtime	Language	Date
1	Thomas Feld	0.01 s	APL	2023-03-08 15:12:29
2	Johan Clarström	0.01 s	APL	2023-03-12 00:20:50
3	Steve Allen	0.01 s	APL	2023-04-25 00:05:54
4	Max NC	0.01 s	APL	2023-09-09 19:40:30
5	Matzuka	0.01 s	APL	2025-04-01 09:57:05
6	Si Jie Tan	0.01 s	APL	2025-12-12 01:43:21

#	User	Runtime	Language	Date
1	Chenzhang Hu	0.01 s	Bash	2023-09-06 16:17:37
2	Thomas Feld	0.01 s	Bash	2023-09-26 08:51:20
3	Chandler McFarland	0.01 s	Bash	2025-02-20 11:46:13
4	Manish shrestha	0.01 s	Bash	2025-04-15 09:01:56

#	User	Runtime	Language	Date
1	Mikael Fiala-Lundström	0.02 s	C#	2021-05-20 11:07:47
2	Maykal Droshev	0.02 s	C#	2021-05-20 13:33:59
3	Ricardo Miguel Bento Gabriel	0.02 s	C#	2021-05-21 23:18:11
4	Per Wendt	0.02 s	C#	2021-05-25 12:33:30
5	Marcos Kirchner	0.02 s	C#	2021-05-29 14:04:56
6	Marcus Östling	0.02 s	C#	2021-05-31 04:53:08
7	markcc	0.02 s	C#	2021-06-01 10:32:31
8	Toby Maynard	0.02 s	C#	2021-06-10 10:58:56
9	Jonas Thomassen	0.02 s	C#	2021-06-12 21:21:24
10	Carson Price	0.02 s	C#	2021-06-16 14:54:20

#	User	Runtime	Language	Date
1	appleby	0.01 s	Common Lisp	2023-04-07 03:53:14
2	Ralf Jonas	0.01 s	Common Lisp	2023-09-07 13:28:42

#	User	Runtime	Language	Date
1	CharsKun	0.01 s	Dart	2023-05-25 09:53:15
2	Christoforos Pantazi	0.01 s	Dart	2023-09-11 13:13:39

#	User	Runtime	Language	Date
1	Sebastian Sternberg	0.04 s	F#	2021-08-23 07:30:44
2	Tim Mondorf	0.04 s	F#	2021-11-28 07:30:58
3	Jacob Harris Cryer Kragh	0.05 s	F#	2022-05-26 13:39:30

#	User	Runtime	Language	Date
1	Suka Isnaini	0.00 s	Go	2023-12-14 16:55:10
2	Jimmy Nejtron	0.02 s	Go	2022-11-16 18:34:59
3	Ahmad Mirdas	0.02 s	Go	2022-12-02 01:08:30
4	Tyler Salmen	0.08 s	Go	2021-05-20 04:14:36
5	Norbert Voelker	0.08 s	Go	2021-05-21 19:55:58
6	Krzysztof Gibuła	0.08 s	Go	2021-05-25 18:39:51
7	dick move	0.08 s	Go	2021-05-29 17:07:27
8	Jahid Hasan Imon	0.08 s	Go	2021-07-26 07:00:00
9	Kok Dith	0.08 s	Go	2021-07-29 09:53:47
10	Lucca Dias	0.08 s	Go	2021-07-29 20:57:41

#	User	Runtime	Language	Date
1	Jinwoo Kim	0.04 s	Java	2024-10-17 20:36:39
2	Guangyi Zhou	0.04 s	Java	2024-11-17 10:15:06
3	Hidden user	0.04 s	Java	2024-12-08 15:20:10
4	Hor Zhu Ming	0.04 s	Java	2025-01-09 08:18:17
5	Todd W. Neller	0.04 s	Java	2025-01-21 21:21:37
6	Goh Zhixuan Jeremiah	0.04 s	Java	2025-02-15 15:58:01
7	Daniel Gutierrez Duarte	0.04 s	Java	2025-03-09 21:53:56
8	Ian Montaño Pardo	0.04 s	Java	2025-04-04 02:19:25
9	Markus Bao	0.04 s	Java	2025-07-22 03:44:14
10	Love Engman	0.05 s	Java	2024-03-17 19:26:37

#	User	Runtime	Language	Date
1	Faisal Rahman	0.04 s	JavaScript (Node.js)	2024-01-30 08:48:12
2	Hidden user	0.04 s	JavaScript (Node.js)	2024-08-22 22:04:08
3	Erlend Raa Vågset	0.04 s	JavaScript (Node.js)	2025-10-23 13:22:11
4	Yassin Swag	0.05 s	JavaScript (Node.js)	2023-12-10 11:13:51
5	John	0.09 s	JavaScript (Node.js)	2022-07-14 23:04:51
6	Martin Chemander	0.09 s	JavaScript (Node.js)	2022-11-26 09:36:07
7	Marko Doroch	0.09 s	JavaScript (Node.js)	2022-12-05 05:09:50
8	Karim Dridi	0.41 s	JavaScript (Node.js)	2022-01-13 22:52:53
9	Antoine Bauri	0.42 s	JavaScript (Node.js)	2021-06-04 13:51:15
10	August Danell Håkansson	0.42 s	JavaScript (Node.js)	2021-07-27 08:01:23

#	User	Runtime	Language	Date
1	Bjørn Chr. Soltvedt	0.02 s	JavaScript (SpiderMonkey)	2021-05-21 09:04:50
2	Peter Menyes	0.02 s	JavaScript (SpiderMonkey)	2021-08-08 18:15:36
3	Gerald Go	0.02 s	JavaScript (SpiderMonkey)	2021-10-19 14:54:58
4	Nicklas Utgaard	0.02 s	JavaScript (SpiderMonkey)	2021-12-22 18:38:18
5	Jimmy Gustafsson	0.02 s	JavaScript (SpiderMonkey)	2022-06-12 11:00:04
6	Alexander Vestin	0.02 s	JavaScript (SpiderMonkey)	2022-10-14 18:07:03
7	Christian Pilegaard Cederquist	0.02 s	JavaScript (SpiderMonkey)	2022-10-30 15:21:22
8	Evan Magill	0.02 s	JavaScript (SpiderMonkey)	2024-04-06 23:09:27
9	Ben Armstrong	0.02 s	JavaScript (SpiderMonkey)	2025-07-16 21:37:23

#	User	Runtime	Language	Date
1	Danny Robinson	0.45 s	Julia	2023-06-22 01:53:20
2	Timothy Gaede	0.62 s	Julia	2024-03-18 18:37:09

#	User	Runtime	Language	Date
1	Jacob Huebner	0.11 s	Kotlin	2021-09-10 19:17:15
2	Aksel Holbek Sørbye	0.12 s	Kotlin	2022-10-15 15:10:54
3	Nicholas Johnson	0.13 s	Kotlin	2021-09-08 21:35:19
4	Roger Bongers	0.14 s	Kotlin	2021-06-26 17:34:48
5	Ola Sundell	0.14 s	Kotlin	2021-07-31 13:46:01
6	Marit van Dijk	0.14 s	Kotlin	2021-09-13 17:23:20
7	Emil Wihlander	0.16 s	Kotlin	2023-05-07 19:55:41
8	Eloy Hernández	0.17 s	Kotlin	2021-08-26 22:28:54
9	Alan Pramuk	0.17 s	Kotlin	2022-08-01 18:17:09
10	Mathias Skallerud Jacobsen	0.18 s	Kotlin	2021-05-27 16:12:52

#	User	Runtime	Language	Date
1	Fredrik Eriksson	0.00 s	OCaml	2024-10-23 13:21:55

#	User	Runtime	Language	Date
1	Hidden user	0.00 s	Odin	2025-04-29 23:32:56

#	User	Runtime	Language	Date
1	Ingemar Ragnemalm	0.00 s	Pascal	2021-05-21 20:53:36
2	David Connolly	0.00 s	Pascal	2021-11-22 13:22:46

#	User	Runtime	Language	Date
1	Saito Ta	0.00 s	Perl	2024-03-29 02:18:00
2	Ahmad Barhamje	0.01 s	Perl	2025-04-19 13:52:15

#	User	Runtime	Language	Date
1	Renate Fiala-Lundström	0.01 s	PHP	2021-05-20 20:00:20
2	Andre Wahyudi	0.01 s	PHP	2022-09-19 09:58:41
3	Petrus Dughem	0.01 s	PHP	2022-12-08 14:24:19
4	Bisesh Heyojoo	0.01 s	PHP	2023-10-27 19:33:57

#	User	Runtime	Language	Date
1	Hakan Kjellerstrand	0.02 s	Prolog	2023-01-19 19:37:14
2	Andriy Zyevakov	0.02 s	Prolog	2023-03-20 16:28:00

#	User	Runtime	Language	Date
1	Hasan Kalzi	0.02 s	Python 2	2022-06-18 18:50:29
2	Thomas Feld	0.03 s	Python 2	2021-05-21 06:27:49
3	Andreas Björklund	0.03 s	Python 2	2021-05-24 18:46:55
4	Johan Lyts	0.03 s	Python 2	2021-05-25 09:38:36
5	Yanmarshus Bachtiar	0.03 s	Python 2	2021-05-29 03:07:24
6	Gibransyah	0.03 s	Python 2	2021-06-15 01:36:04
7	Andrei Stoica	0.03 s	Python 2	2021-09-08 09:34:02
8	Grant Josenhans	0.03 s	Python 2	2022-01-20 18:20:56
9	Sivasankaran D	0.07 s	Python 2	2025-08-04 11:50:47

#	User	Runtime	Language	Date
1	Negar Saeedi	0.04 s	Python 3	2022-06-04 14:26:45
2	Khang Trần	0.04 s	Python 3	2022-06-05 10:07:33
3	András Biczó	0.04 s	Python 3	2022-06-05 15:43:37
4	Josephine Dunker	0.04 s	Python 3	2022-06-05 18:18:07
5	Dawa Tenzin Namgay	0.04 s	Python 3	2022-06-06 04:07:16
6	Hidden user	0.04 s	Python 3	2022-06-06 04:18:48
7	Peder Ørmen Bukaasen	0.04 s	Python 3	2022-06-06 11:38:26
8	Hesamedin Alemifar	0.04 s	Python 3	2022-06-06 12:40:35
9	Johan Kjellström	0.04 s	Python 3	2022-06-07 09:47:18
10	Hidden user	0.04 s	Python 3	2022-06-07 15:03:31

#	User	Runtime	Language	Date
1	Jonathan Ogden	0.05 s	Ruby	2021-05-26 15:05:33
2	Hadi Qovaizi	0.05 s	Ruby	2021-07-08 20:59:18
3	Hidden user	0.05 s	Ruby	2021-08-31 11:16:06
4	Nathan Derr	0.05 s	Ruby	2021-09-02 21:38:18
5	Troy Sornson	0.05 s	Ruby	2022-01-04 01:01:32
6	Régis Hanol	0.05 s	Ruby	2022-01-07 11:33:13
7	TobiasZ	0.05 s	Ruby	2022-01-20 17:48:37
8	Patrick Elsen	0.05 s	Ruby	2022-09-09 12:50:00
9	Eugen Neagoe	0.05 s	Ruby	2023-04-05 22:22:34
10	Christian Pilegaard Cederquist	0.06 s	Ruby	2022-10-30 15:27:03

#	User	Runtime	Language	Date
1	Jhony Andreas	0.04 s	Visual Basic	2023-07-08 17:26:00

#	User	Runtime	Language	Date
1	Grettir Heimisson	0.00 s	Zig	2025-10-28 18:07:54

#	User	Length	Language	Date
1	Thomas Feld	14	APL	2023-09-13 07:17:18
2	Johan Clarström	16	APL	2023-03-12 00:20:50
3	Steve Allen	16	APL	2023-04-25 00:07:22
4	Max NC	16	APL	2023-09-09 19:40:30
5	Si Jie Tan	20	APL	2025-12-12 01:43:21
6	Matzuka	25	APL	2025-04-01 10:10:48

#	User	Length	Language	Date
1	Chenzhang Hu	22	Bash	2025-09-12 19:02:21
2	Thomas Feld	24	Bash	2023-09-26 08:53:08
3	Manish shrestha	195	Bash	2025-04-15 09:01:56
4	Chandler McFarland	505	Bash	2025-02-20 11:46:13

#	User	Length	Language	Date
1	Martin Blom	90	C	2023-09-17 09:57:38
2	Benjamin Iserman	94	C	2023-03-01 20:36:18
3	Sawyer Frie	150	C	2023-03-01 19:13:56
4	Oliver Noreklev	163	C	2025-09-27 16:59:32
5	Caeden Whitaker	222	C	2024-07-19 15:02:23
6	Oliver Ruste Jahren	225	C	2023-05-20 11:15:12
7	Raymond Yang	253	C	2021-06-25 20:51:16
8	Ximun Castoreo	254	C	2022-01-06 14:53:20
9	James Rettie	256	C	2022-10-25 06:35:48
10	Colton Palmer	267	C	2023-08-09 14:54:17

#	User	Length	Language	Date
1	Mikael Palokangas	104	C#	2023-08-07 17:51:08
2	Theodore Glenn	154	C#	2023-02-18 18:42:29
3	Pontus Magnusson	247	C#	2024-03-26 21:38:53
4	Benny Antonsson	257	C#	2021-10-18 21:30:14
5	Aiden Bilyeu	268	C#	2023-02-17 16:57:27
6	Mhmt Tan	282	C#	2023-09-01 21:58:16
7	Jimmy Roche	307	C#	2021-06-24 17:33:58
8	Hidden user	314	C#	2022-06-05 10:36:45
9	Göran Andersson	319	C#	2022-05-06 14:12:06
10	Marcus Sebastian Emil Holmgaard	331	C#	2023-06-21 18:53:55

#	User	Length	Language	Date
1	Frans Meulenbroeks	117	C++	2024-11-10 21:55:39
2	Adil Rasiyani	137	C++	2023-03-02 09:04:29
3	a_b__c	142	C++	2021-08-17 17:07:21
4	Jordan A Hopkins	148	C++	2023-07-25 17:53:45
5	Evan Michael Bailey	157	C++	2024-02-12 23:56:17
6	Rajath	158	C++	2022-11-14 23:01:27
7	traxex	164	C++	2021-10-03 20:12:03
8	Hidden user	173	C++	2022-11-21 08:54:34
9	Lukáš Jiřiště	184	C++	2023-01-31 09:28:48
10	Wlit eat shit	185	C++	2022-03-09 13:42:05

#	User	Length	Language	Date
1	Ralf Jonas	309	Common Lisp	2023-09-07 13:28:42
2	appleby	325	Common Lisp	2023-04-07 03:53:14

#	User	Length	Language	Date
1	CharsKun	206	Dart	2023-05-25 09:53:15
2	Christoforos Pantazi	224	Dart	2023-09-11 13:13:39

#	User	Length	Language	Date
1	Tim Mondorf	163	F#	2021-11-28 07:30:58
2	Jacob Harris Cryer Kragh	221	F#	2022-05-26 13:39:30
3	Sebastian Sternberg	267	F#	2021-08-23 07:30:44

#	User	Length	Language	Date
1	Hidden user	229	Go	2021-12-15 11:12:18
2	dick move	237	Go	2021-05-29 17:07:27
3	Suka Isnaini	260	Go	2023-12-14 16:55:10
4	Lucca Dias	263	Go	2021-07-29 20:57:41
5	Hidden user	268	Go	2022-03-11 12:03:37
6	Andey Robins	292	Go	2021-08-23 14:47:30
7	Muhammad Auliya	294	Go	2022-03-25 12:05:21
8	Hidden user	298	Go	2021-10-09 19:49:02
9	Nyamdavaa Amar	320	Go	2022-04-23 21:49:19
10	Rayson Tan	335	Go	2021-08-02 05:57:10

#	User	Length	Language	Date
1	John Doe	59	Haskell	2023-04-11 17:53:13
2	Matthew A Johnson	65	Haskell	2022-12-02 15:50:12
3	Rudy Matela	67	Haskell	2023-09-11 19:10:34
4	Elizabeth Doughty	88	Haskell	2024-02-05 07:26:00
5	Kristian Sørdal	97	Haskell	2023-01-13 11:46:09
6	Morten Lohne	106	Haskell	2021-08-17 11:22:36
7	Azeez Daoud	111	Haskell	2023-01-26 08:25:09
8	Monique Oliveira	113	Haskell	2021-05-23 05:26:08
9	Steinar Simonnes	116	Haskell	2023-11-02 21:25:03
10	Hidden user	124	Haskell	2024-01-31 18:26:41

#	User	Length	Language	Date
1	Nicholas Bui	268	Java	2022-06-05 01:51:59
2	Andrew Thomas Hupp	291	Java	2022-01-14 00:32:27
3	Magnus Tønnessen	296	Java	2021-05-27 10:10:42
4	Dakota South	301	Java	2022-11-03 18:15:22
5	Lim Ting Kai	308	Java	2023-05-29 13:07:21
6	Markus Wrang	310	Java	2023-04-09 13:46:38
7	Brendan Cao	315	Java	2024-10-16 17:45:13
8	Frederick Phillip Javier	334	Java	2021-10-16 07:38:09
9	Kyubin Han	339	Java	2024-03-21 05:41:43
10	Sophia Schober-Longhi	342	Java	2024-03-21 00:53:29

#	User	Length	Language	Date
1	Erlend Raa Vågset	128	JavaScript (Node.js)	2025-10-23 13:22:11
2	Peter Kedemo	234	JavaScript (Node.js)	2022-01-02 10:02:19
3	Hidden user	246	JavaScript (Node.js)	2023-01-27 04:20:04
4	Karim Dridi	265	JavaScript (Node.js)	2022-01-13 22:52:53
5	Faisal Rahman	293	JavaScript (Node.js)	2024-01-30 08:48:12
6	Antoine Bauri	357	JavaScript (Node.js)	2021-06-04 13:51:15
7	Ralf Leistad	391	JavaScript (Node.js)	2021-08-04 18:34:23
8	Howard Tin Chi Chan	472	JavaScript (Node.js)	2022-01-11 19:48:19
9	Ali	480	JavaScript (Node.js)	2021-12-18 11:27:30
10	Jonathan Hannerfeldt	480	JavaScript (Node.js)	2022-04-15 09:09:23

#	User	Length	Language	Date
1	Christian Pilegaard Cederquist	36	JavaScript (SpiderMonkey)	2022-10-30 15:21:22
2	Ben Armstrong	93	JavaScript (SpiderMonkey)	2025-07-16 21:37:23
3	Jimmy Gustafsson	107	JavaScript (SpiderMonkey)	2022-06-12 11:00:04
4	Bjørn Chr. Soltvedt	192	JavaScript (SpiderMonkey)	2021-05-21 09:04:50
5	Peter Menyes	204	JavaScript (SpiderMonkey)	2021-08-08 18:15:36
6	Evan Magill	219	JavaScript (SpiderMonkey)	2024-04-06 23:09:27
7	Alexander Vestin	235	JavaScript (SpiderMonkey)	2022-10-14 18:07:03
8	Nicklas Utgaard	375	JavaScript (SpiderMonkey)	2021-12-22 18:38:18
9	Gerald Go	457	JavaScript (SpiderMonkey)	2021-10-19 14:54:58

#	User	Length	Language	Date
1	Danny Robinson	52	Julia	2023-06-22 01:53:20
2	Timothy Gaede	189	Julia	2024-03-18 18:37:09

#	User	Length	Language	Date
1	Yao Wang	98	Kotlin	2022-06-05 04:43:21
2	Nicholas Johnson	105	Kotlin	2021-09-29 22:31:12
3	Sergey Jakobsen	117	Kotlin	2021-05-21 17:53:54
4	Roger Bongers	136	Kotlin	2021-06-26 17:34:48
5	Lauren Pace	144	Kotlin	2021-06-10 17:38:10
6	Albert Pala	148	Kotlin	2021-05-25 22:33:43
7	Troy Warmboe	157	Kotlin	2021-10-09 00:28:22
8	Mathias Skallerud Jacobsen	168	Kotlin	2021-05-27 16:12:52
9	Anders B. Clausen	174	Kotlin	2021-07-03 22:43:01
10	Magnus Tønnessen	175	Kotlin	2021-09-08 14:22:47

#	User	Length	Language	Date
1	Fredrik Eriksson	269	OCaml	2024-10-23 13:21:55

#	User	Length	Language	Date
1	Hidden user	355	Odin	2025-04-29 23:32:56

#	User	Length	Language	Date
1	Ingemar Ragnemalm	305	Pascal	2021-05-21 20:53:36
2	David Connolly	445	Pascal	2021-11-22 13:22:46

#	User	Length	Language	Date
1	Saito Ta	20	Perl	2024-03-29 02:18:00
2	Ahmad Barhamje	1542	Perl	2025-04-19 13:52:15

#	User	Length	Language	Date
1	Renate Fiala-Lundström	143	PHP	2021-05-20 20:00:20
2	Andre Wahyudi	397	PHP	2022-09-19 09:58:41
3	Petrus Dughem	407	PHP	2022-12-08 14:24:19
4	Bisesh Heyojoo	659	PHP	2023-10-27 19:33:57

#	User	Length	Language	Date
1	Hakan Kjellerstrand	97	Prolog	2023-03-16 18:27:31
2	Andriy Zyevakov	163	Prolog	2023-03-20 16:28:00

#	User	Length	Language	Date
1	Thomas Feld	45	Python 2	2021-05-21 06:28:27
2	Sivasankaran D	55	Python 2	2025-08-04 11:50:47
3	Andreas Björklund	90	Python 2	2021-05-24 18:46:55
4	Johan Lyts	115	Python 2	2021-05-25 09:38:36
5	Yanmarshus Bachtiar	132	Python 2	2021-05-29 03:07:24
6	Grant Josenhans	150	Python 2	2022-01-20 18:20:56
7	Andrei Stoica	164	Python 2	2021-09-08 09:34:02
8	Hasan Kalzi	344	Python 2	2021-06-21 08:55:31
9	Gibransyah	390	Python 2	2021-06-15 01:36:04

#	User	Length	Language	Date
1	Błażej Dariusz Roszkowski	36	Python 3	2022-11-26 23:19:40
2	Benjamin Iserman	36	Python 3	2023-03-01 20:05:22
3	Clement Oh	36	Python 3	2023-06-02 14:26:29
4	Kevin Gomez	36	Python 3	2023-07-23 23:16:19
5	Carl Pittenger	36	Python 3	2024-03-24 02:10:43
6	German Ivkovich	36	Python 3	2025-04-20 20:35:45
7	Hidden user	37	Python 3	2023-01-09 14:55:54
8	Ritwin Narra	38	Python 3	2021-06-18 01:22:31
9	Erik Heimdal	38	Python 3	2022-11-24 22:49:28
10	Gustav Elmqvist	38	Python 3	2023-03-16 10:49:27

#	User	Length	Language	Date
1	Russell Ng	25	Ruby	2025-06-01 09:03:17
2	Thomas Feld	26	Ruby	2022-11-01 07:42:29
3	Hakan Kjellerstrand	27	Ruby	2023-03-17 09:53:25
4	Christian Pilegaard Cederquist	30	Ruby	2022-10-30 15:27:03
5	Frederik Petersen	36	Ruby	2024-03-26 19:47:30
6	Patrick Elsen	40	Ruby	2022-09-09 12:50:00
7	Alexander Bilde Pedersen	42	Ruby	2023-04-06 17:09:26
8	Régis Hanol	53	Ruby	2022-01-07 11:33:13
9	Jonathan Ogden	59	Ruby	2021-05-26 15:05:33
10	Hidden user	67	Ruby	2022-12-10 04:42:26

#	User	Length	Language	Date
1	Vincent Lagerros	147	Rust	2024-12-03 23:15:06
2	JOAO VITOR GUIMARAES COSTA	226	Rust	2022-12-22 00:14:40
3	Pankajkumar Patro	282	Rust	2024-07-18 20:32:33
4	David Zacek	314	Rust	2021-05-20 17:07:31
5	Dalton Cole	316	Rust	2021-09-12 23:17:52
6	Kjartan Óli Ágústsson	334	Rust	2021-08-10 20:03:44
7	Selim Yetkin	335	Rust	2023-08-11 22:39:01
8	Bas Dirks	349	Rust	2021-12-29 20:43:25
9	Simon Grünwald	360	Rust	2023-07-10 19:03:18
10	Connor Nagle	367	Rust	2023-04-24 22:46:12

#	User	Length	Language	Date
1	Jhony Andreas	540	Visual Basic	2023-07-08 17:26:00

#	User	Length	Language	Date
1	Grettir Heimisson	2711	Zig	2025-10-28 18:07:54

Solution running time distribution