Problem A
Server — Problem Statistics

Back to problem description

Submissions	19488
Accepted submissions	7917
Submission ratio	40.62%
Authors	7462
Full solves [?]	6937
Full solve Ratio	92.96%

#	User	Runtime	Language	Date
1	Michael Wichlinski	0.00 s	Ada	2025-04-10 03:00:34

#	User	Runtime	Language	Date
1	Danny Robinson	0.01 s	Bash	2023-09-02 10:40:48
2	Manish shrestha	0.01 s	Bash	2025-04-15 11:13:36
3	Chenzhang Hu	0.01 s	Bash	2025-09-12 15:53:39

#	User	Runtime	Language	Date
1	Jens Mossig	0.02 s	C#	2015-12-25 22:17:04
2	Faisal Rahman	0.02 s	C#	2016-01-15 01:01:34
3	Sean Gorsky	0.02 s	C#	2016-02-09 00:57:30
4	Soonfay Yee	0.02 s	C#	2016-02-09 01:35:03
5	Joe Amenta	0.02 s	C#	2016-04-05 04:15:30
6	Khin Nyunt	0.02 s	C#	2016-04-17 06:05:49
7	Raja Sanjeev Kumar Nakka	0.02 s	C#	2016-04-29 20:09:55
8	lobo	0.02 s	C#	2016-05-22 08:53:02
9	Robert Low	0.02 s	C#	2016-07-16 11:51:42
10	Duelene Olson	0.02 s	C#	2016-08-04 04:51:26

#	User	Runtime	Language	Date
1	David Cawthon	0.02 s	Common Lisp	2019-04-10 04:04:11

#	User	Runtime	Language	Date
1	Jacob Harris Cryer Kragh	0.03 s	F#	2022-07-14 15:38:28

#	User	Runtime	Language	Date
1	Arunangshu Biswas	0.00 s	Go	2023-09-20 05:28:37
2	Suka Isnaini	0.00 s	Go	2023-12-05 16:57:08
3	Kiki Ibrahim	0.00 s	Go	2024-05-05 13:25:12
4	Hidden user	0.00 s	Go	2024-05-08 07:37:17
5	Sunho Kim	0.00 s	Go	2024-06-17 09:04:41
6	Jimmy Nejtron	0.00 s	Go	2024-12-29 13:20:14
7	Matthias Doepmann	0.00 s	Go	2025-04-15 20:41:04
8	Sebastian Jimenez	0.00 s	Go	2025-04-24 05:53:18
9	MARIA JOSE MORALES AVALOS	0.00 s	Go	2025-04-24 09:30:38
10	Diamond	0.02 s	Go	2022-11-19 05:17:29

#	User	Runtime	Language	Date
1	Hidden user	0.04 s	Java	2024-10-21 20:52:34
2	Jessica	0.04 s	Java	2024-10-21 20:55:09
3	Guangyi Zhou	0.04 s	Java	2024-12-17 15:20:27
4	Amidala Hoffmén	0.04 s	Java	2025-02-07 16:14:09
5	Hidden user	0.04 s	Java	2025-02-12 14:01:20
6	Hidden user	0.04 s	Java	2025-04-17 20:02:19
7	Elaica Dela Cruz	0.04 s	Java	2025-06-25 12:26:13
8	Chris Wu	0.05 s	Java	2015-10-24 19:04:37
9	Eskil Jarlskog	0.05 s	Java	2015-10-24 19:05:52
10	Kensen Shi	0.05 s	Java	2015-10-24 19:11:20

#	User	Runtime	Language	Date
1	Hamza Hasbi	0.04 s	JavaScript (Node.js)	2023-10-14 18:28:17
2	Gonçalo Novo	0.04 s	JavaScript (Node.js)	2025-07-24 13:13:24
3	Shaw Robillard	0.04 s	JavaScript (Node.js)	2025-07-26 16:25:38
4	Dario Delle Donne	0.05 s	JavaScript (Node.js)	2018-12-18 11:59:34
5	Tomáš Necky Necuda	0.05 s	JavaScript (Node.js)	2019-02-05 21:54:22
6	console.log	0.05 s	JavaScript (Node.js)	2019-03-08 20:46:12
7	Gurpartap Singh Bhatti	0.05 s	JavaScript (Node.js)	2019-05-26 14:22:34
8	Hidden user	0.05 s	JavaScript (Node.js)	2024-09-01 18:12:16
9	Jerry Hu	0.06 s	JavaScript (Node.js)	2019-02-15 16:08:00
10	Emil Larsson	0.06 s	JavaScript (Node.js)	2019-06-16 02:29:23

#	User	Runtime	Language	Date
1	Peter Kedemo	0.01 s	JavaScript (SpiderMonkey)	2015-12-19 23:46:24
2	Bjørn Chr. Soltvedt	0.01 s	JavaScript (SpiderMonkey)	2015-12-31 18:50:12
3	Hidden user	0.01 s	JavaScript (SpiderMonkey)	2016-01-07 20:41:17
4	Ionel Hindorean	0.01 s	JavaScript (SpiderMonkey)	2016-12-02 12:10:16
5	Christopher Tse	0.01 s	JavaScript (SpiderMonkey)	2017-03-24 01:28:23
6	Alan Delaney	0.01 s	JavaScript (SpiderMonkey)	2017-04-12 02:40:24
7	Peter Menyes	0.01 s	JavaScript (SpiderMonkey)	2017-08-25 16:41:33
8	Hai Yang Xu	0.01 s	JavaScript (SpiderMonkey)	2017-09-24 05:05:46
9	Desireé af Geijerstam	0.01 s	JavaScript (SpiderMonkey)	2018-01-16 22:25:13
10	Dilawar Mahmood	0.01 s	JavaScript (SpiderMonkey)	2018-01-27 19:20:57

#	User	Runtime	Language	Date
1	Timothy Gaede	0.53 s	Julia	2024-05-31 05:48:19

#	User	Runtime	Language	Date
1	Thanh Le	0.11 s	Kotlin	2021-07-13 19:27:39
2	Jahid Hasan Imon	0.12 s	Kotlin	2020-07-02 00:30:35
3	Jacob Huebner	0.13 s	Kotlin	2021-05-31 06:19:31
4	Léo Eduardo Silva	0.14 s	Kotlin	2020-09-12 01:34:36
5	Brilian Ade Putra	0.14 s	Kotlin	2021-03-03 17:07:32
6	Gaurav Tyagi	0.15 s	Kotlin	2018-09-07 00:43:00
7	Dayan Ruben Gonzalez	0.15 s	Kotlin	2020-09-28 01:50:02
8	Nico Metger	0.15 s	Kotlin	2021-10-22 18:24:50
9	Ahmed Waseem Saeed	0.16 s	Kotlin	2021-12-18 14:01:19
10	Phường Lên	0.18 s	Kotlin	2019-12-25 05:05:09

#	User	Runtime	Language	Date
1	Remigijus Jodelis	0.00 s	Nim	2025-07-23 15:05:02

#	User	Runtime	Language	Date
1	Fredrik Eriksson	0.00 s	OCaml	2024-11-03 02:30:38
2	Hidden user	0.00 s	OCaml	2025-06-22 20:13:24

#	User	Runtime	Language	Date
1	David Connolly	0.00 s	Pascal	2017-08-23 17:53:24
2	Ingemar Ragnemalm	0.00 s	Pascal	2017-09-04 07:54:29
3	Vova Podkorytov	0.00 s	Pascal	2017-12-20 16:47:41
4	Egor Shchetinin	0.00 s	Pascal	2018-01-15 15:13:17
5	林達炘4D20 Lam Tat Yan	0.00 s	Pascal	2020-02-14 07:30:54

#	User	Runtime	Language	Date
1	Steven D. Wilson	0.01 s	PHP	2016-11-25 18:27:46
2	Markus Weller	0.01 s	PHP	2019-02-21 13:03:08
3	Abdullah Akbar	0.01 s	PHP	2019-04-30 20:29:12
4	Jonas Lindenskov Nielsen	0.01 s	PHP	2019-09-21 18:14:20
5	Fluff Abrahamsson	0.01 s	PHP	2020-10-01 21:34:03
6	cojonas1	0.01 s	PHP	2021-02-02 16:40:19
7	devina thessalonica	0.01 s	PHP	2021-05-01 06:30:23
8	wendy lau	0.01 s	PHP	2021-05-09 11:04:53
9	Ivan Mintarja	0.01 s	PHP	2021-08-02 18:30:13
10	daniel pranoto	0.01 s	PHP	2021-08-02 20:45:28

#	User	Runtime	Language	Date
1	Andriy Zyevakov	0.01 s	Prolog	2016-03-30 23:16:16
2	Hadi Qovaizi	0.01 s	Prolog	2016-04-17 19:25:31
3	Hakan Kjellerstrand	0.02 s	Prolog	2023-02-06 08:40:09

#	User	Runtime	Language	Date
1	Christofer Ohlsson	0.02 s	Python 2	2015-10-24 19:45:02
2	Frederik Højholt	0.02 s	Python 2	2015-10-27 19:41:01
3	Asger Hautop Drewsen	0.02 s	Python 2	2015-11-03 21:28:36
4	Carl Martin Rosenberg	0.02 s	Python 2	2015-11-08 22:44:30
5	Hans Rusten	0.02 s	Python 2	2015-11-29 13:35:09
6	Urban Pettersson	0.02 s	Python 2	2016-01-20 20:03:56
7	Ryan Godisman	0.02 s	Python 2	2016-02-09 00:38:04
8	Arsh Raza	0.02 s	Python 2	2016-02-09 00:42:10
9	Aleksandr Dobrev	0.02 s	Python 2	2016-02-22 19:20:22
10	Alexander Teno	0.02 s	Python 2	2016-02-25 22:17:07

#	User	Runtime	Language	Date
1	Charles Zinn	0.02 s	Python 3	2015-10-24 19:04:12
2	Emil Riis Hansen	0.02 s	Python 3	2015-10-28 22:21:56
3	曾威凱	0.02 s	Python 3	2015-11-06 07:57:24
4	Kevin Froman	0.02 s	Python 3	2015-11-20 19:39:55
5	Tammo Behrends	0.02 s	Python 3	2015-12-01 12:09:32
6	Martin Stensgård	0.02 s	Python 3	2016-01-24 06:04:57
7	Wayne	0.02 s	Python 3	2016-01-27 10:26:23
8	Joshua Zygmunt	0.02 s	Python 3	2016-02-03 08:33:20
9	Joshua Martin Tjahjadi	0.02 s	Python 3	2016-02-05 19:27:45
10	Heidi Sand	0.02 s	Python 3	2016-02-07 15:33:47

#	User	Runtime	Language	Date
1	Casper Christensen	0.03 s	Ruby	2016-02-04 16:05:50
2	Gerry Hall	0.03 s	Ruby	2016-03-27 21:27:44
3	Lasse Berglund	0.03 s	Ruby	2016-04-01 12:31:21
4	Erik Rydbert	0.03 s	Ruby	2016-07-12 02:16:15
5	Hidden user	0.03 s	Ruby	2016-08-12 08:48:25
6	Chris Weston	0.03 s	Ruby	2016-09-29 15:40:08
7	Clifford Owino	0.03 s	Ruby	2017-05-25 07:24:56
8	Daniel Harder	0.04 s	Ruby	2018-09-01 03:16:34
9	Hidden user	0.04 s	Ruby	2018-10-12 20:28:44
10	Uğurcan Eser	0.04 s	Ruby	2018-11-12 18:56:16

#	User	Runtime	Language	Date
1	Anton J Olsson	0.09 s	TypeScript	2023-08-06 17:18:53

#	User	Runtime	Language	Date
1	Joe Blower	0.00 s	Zig	2025-05-23 03:07:34

#	User	Length	Language	Date
1	Michael Wichlinski	1085	Ada	2025-04-10 03:00:34

#	User	Length	Language	Date
1	Chenzhang Hu	45	Bash	2025-09-12 15:53:39
2	Danny Robinson	62	Bash	2023-09-02 10:40:48
3	Manish shrestha	231	Bash	2025-04-15 11:13:36

#	User	Length	Language	Date
1	Martin Blom	109	C	2023-11-14 21:33:48
2	Magnus Wass	184	C	2020-03-16 22:10:43
3	Hidden user	188	C	2017-07-13 22:50:18
4	Koulury Benarji	194	C	2018-11-07 08:34:50
5	Wesley Stephanak	196	C	2019-02-05 07:04:20
6	Yap Yi Juinn Jacelyn	197	C	2016-12-17 05:55:15
7	huy lý	200	C	2022-10-04 08:21:06
8	Yogindra Addanki	208	C	2020-01-20 15:23:01
9	Nagata Parama Aptana	212	C	2021-08-10 17:14:19
10	Muhammed Ali Aytürk	215	C	2020-03-12 22:37:55

#	User	Length	Language	Date
1	Medha Alla	317	C#	2023-10-24 17:01:32
2	Krishnasai Chaluvadi	317	C#	2023-10-29 17:21:36
3	Sravani Dondapati	332	C#	2023-10-27 18:59:34
4	bhanu prakash konda	347	C#	2023-10-25 04:22:49
5	Kunwei Zhang	359	C#	2018-06-12 11:57:46
6	Manoj Naidu Arasada	395	C#	2023-10-30 00:37:46
7	Lucía María Alvarez Sánchez	405	C#	2023-04-19 01:33:20
8	Wyatt	405	C#	2023-04-29 20:34:55
9	SINDHURAALLA	405	C#	2023-10-24 15:48:31
10	Fernanda Ferrer Ortega	407	C#	2023-02-26 07:29:10

#	User	Length	Language	Date
1	Frans Meulenbroeks	116	C++	2024-11-15 09:11:37
2	黃太陽	157	C++	2022-02-25 19:29:23
3	Chase Hinesman	184	C++	2017-10-06 01:18:06
4	Admasu Abera	189	C++	2019-10-04 08:44:50
5	Kaiyue Li	192	C++	2020-06-12 16:15:15
6	Abdul Malik Nurrokhman	193	C++	2016-11-22 08:26:48
7	Oskar Haarklou Veileborg	196	C++	2015-11-06 12:53:31
8	Chur Zhe Yaw	199	C++	2019-07-03 08:47:13
9	a_b__c	199	C++	2021-08-15 20:31:25
10	Hoàng Bá Tuân	200	C++	2016-10-28 06:44:41

#	User	Length	Language	Date
1	David Cawthon	330	Common Lisp	2019-04-10 04:04:11

#	User	Length	Language	Date
1	Jacob Harris Cryer Kragh	441	F#	2022-07-14 15:38:28

#	User	Length	Language	Date
1	Suka Isnaini	213	Go	2023-12-05 16:57:08
2	Reza Morsali	256	Go	2018-12-31 12:30:49
3	Kellen Watt	259	Go	2015-10-24 19:43:58
4	dick move	271	Go	2021-05-09 23:10:53
5	Bistok Diiel Lelono	288	Go	2021-04-18 06:42:57
6	ahmad rifai	296	Go	2021-08-05 08:37:09
7	Mohammad Ghifari Yusuf	316	Go	2021-04-05 14:08:00
8	Adam Evans	323	Go	2016-01-30 21:39:53
9	rizky alviandra	331	Go	2021-06-04 06:55:57
10	Mohammad Ghifari Yusuf	340	Go	2021-04-05 14:05:54

#	User	Length	Language	Date
1	Birk Tjelmeland	128	Haskell	2017-08-05 19:02:34
2	Steinar Simonnes	132	Haskell	2024-01-17 16:48:40
3	Øyvind Almli	173	Haskell	2021-09-22 21:44:17
4	Sebastian Banert	173	Haskell	2023-09-18 02:13:15
5	Peter Deal	181	Haskell	2016-05-12 21:59:21
6	Matthew Johnson	182	Haskell	2017-02-04 07:17:00
7	Agus Sentosa Hermawan	183	Haskell	2020-01-09 01:19:40
8	Anthony Clays	196	Haskell	2016-12-04 21:06:25
9	Lieven Marchand	208	Haskell	2017-09-15 21:02:38
10	Vasiliy Kevroletin	216	Haskell	2018-05-15 08:44:59

#	User	Length	Language	Date
1	Lim Ting Kai	267	Java	2023-06-04 23:41:36
2	Monica Wei	296	Java	2015-10-24 19:08:57
3	Benie Agonoy	306	Java	2018-10-21 04:55:22
4	Keith Raghubar	310	Java	2016-02-09 00:55:27
5	Khant Sithu Zaw	312	Java	2019-02-12 22:39:29
6	Elliot Beatty	315	Java	2018-09-26 14:33:06
7	Robert Lee	315	Java	2018-10-03 00:47:58
8	daniel pranoto	315	Java	2021-08-02 18:24:42
9	Shandy Siswandi	315	Java	2021-08-13 15:41:11
10	Hidden user	315	Java	2024-04-17 19:46:00

#	User	Length	Language	Date
1	Aidan Michalos	388	JavaScript (Node.js)	2022-04-07 03:35:11
2	Shaw Robillard	406	JavaScript (Node.js)	2025-07-26 16:25:38
3	Emil Larsson	474	JavaScript (Node.js)	2019-06-16 02:29:23
4	Christopher Walther	481	JavaScript (Node.js)	2021-04-10 00:53:25
5	Kevin Ma	510	JavaScript (Node.js)	2020-07-06 23:39:49
6	William Lim	514	JavaScript (Node.js)	2021-05-18 11:43:41
7	Hovhannes Kantuni	544	JavaScript (Node.js)	2021-03-13 02:59:24
8	syauqi fuadi	550	JavaScript (Node.js)	2021-05-18 10:34:50
9	Muhammad Taufiq Febrianto	551	JavaScript (Node.js)	2021-07-02 11:12:35
10	Cliff A2312235	570	JavaScript (Node.js)	2021-02-22 22:58:32

#	User	Length	Language	Date
1	Jimmy Gustafsson	123	JavaScript (SpiderMonkey)	2024-06-17 11:39:38
2	Evan Magill	131	JavaScript (SpiderMonkey)	2024-04-22 03:15:36
3	Christian Pilegaard Cederquist	137	JavaScript (SpiderMonkey)	2023-01-07 11:45:46
4	Hidden user	184	JavaScript (SpiderMonkey)	2024-09-06 20:33:24
5	Emily Krommendyk	184	JavaScript (SpiderMonkey)	2024-09-09 19:59:46
6	Zachary DeStefano	205	JavaScript (SpiderMonkey)	2018-09-24 21:34:17
7	Johannes Strelen	205	JavaScript (SpiderMonkey)	2018-12-06 19:18:11
8	Zach Tschetter	208	JavaScript (SpiderMonkey)	2023-04-21 01:05:11
9	Desireé af Geijerstam	213	JavaScript (SpiderMonkey)	2018-01-16 22:25:13
10	Brandon Chov	218	JavaScript (SpiderMonkey)	2024-09-06 20:33:47

#	User	Length	Language	Date
1	Timothy Gaede	389	Julia	2024-05-31 05:48:19

#	User	Length	Language	Date
1	Yang Tang	209	Kotlin	2023-07-29 07:48:49
2	Troy Warmboe	233	Kotlin	2023-04-11 16:27:02
3	Einar Kjellback	258	Kotlin	2019-12-15 14:58:57
4	Phường Lên	300	Kotlin	2019-12-25 05:05:09
5	Maicon Dall'Agnol	323	Kotlin	2020-09-11 22:41:31
6	Adam Rankin	350	Kotlin	2023-05-04 07:51:36
7	Sarek Høverstad Skotåm	359	Kotlin	2020-10-22 20:11:04
8	Stélvio Carvalho	367	Kotlin	2025-07-25 15:32:59
9	Dayan Ruben Gonzalez	373	Kotlin	2020-09-28 01:50:02
10	Dmitry Shostak	377	Kotlin	2018-06-22 08:41:22

#	User	Length	Language	Date
1	Remigijus Jodelis	394	Nim	2025-07-23 15:05:02

#	User	Length	Language	Date
1	Fredrik Eriksson	409	OCaml	2024-11-03 02:30:38
2	Hidden user	505	OCaml	2025-06-22 20:13:24

#	User	Length	Language	Date
1	Ingemar Ragnemalm	292	Pascal	2017-09-04 07:54:29
2	林達炘4D20 Lam Tat Yan	360	Pascal	2020-02-14 07:30:54
3	Vova Podkorytov	372	Pascal	2017-12-20 16:47:41
4	Egor Shchetinin	376	Pascal	2018-01-15 15:13:17
5	David Connolly	927	Pascal	2017-08-23 17:53:24

#	User	Length	Language	Date
1	Renate	236	PHP	2023-07-04 00:03:26
2	Fluff Abrahamsson	288	PHP	2020-10-01 21:34:03
3	Jonas Lindenskov Nielsen	343	PHP	2019-09-21 18:14:20
4	Steven D. Wilson	352	PHP	2016-11-25 18:27:46
5	Markus Weller	399	PHP	2019-02-21 13:03:08
6	cojonas1	414	PHP	2021-02-02 16:40:19
7	Abdullah Akbar	416	PHP	2019-04-30 20:29:12
8	Harvin Pratama	448	PHP	2021-08-17 16:51:10
9	devina thessalonica	488	PHP	2021-05-01 06:30:23
10	Daniel Pranoto	488	PHP	2021-08-02 21:02:53

#	User	Length	Language	Date
1	Hakan Kjellerstrand	227	Prolog	2023-02-06 08:42:10
2	Andriy Zyevakov	300	Prolog	2016-03-30 23:16:16
3	Hadi Qovaizi	2517	Prolog	2016-04-17 19:25:31

#	User	Length	Language	Date
1	Thomas Feld	122	Python 2	2019-08-19 12:33:18
2	Andreas Björklund	137	Python 2	2019-05-16 22:17:39
3	Hidden user	147	Python 2	2016-07-08 19:36:53
4	Syed Sarfaraz Akhtar	153	Python 2	2018-09-15 18:08:30
5	Haggai Liu	161	Python 2	2017-01-10 22:08:00
6	Cole Bite	161	Python 2	2017-03-08 20:48:42
7	Johann Ly	161	Python 2	2018-04-09 01:53:20
8	Jesper Öqvist	161	Python 2	2018-10-20 10:48:27
9	Johan Lyts	164	Python 2	2019-03-03 22:09:50
10	Peter Sofronas	170	Python 2	2017-08-25 19:20:40

#	User	Length	Language	Date
1	Clement Oh	84	Python 3	2023-05-22 16:36:22
2	Lasse Letager Hansen	103	Python 3	2023-07-26 19:44:29
3	Magnus Hokland Hegdahl	107	Python 3	2023-11-16 01:17:46
4	Hidden user	109	Python 3	2025-01-19 21:28:58
5	Charles Ancheta	110	Python 3	2023-04-07 22:17:04
6	Guk Yi Siong	113	Python 3	2023-12-24 15:14:06
7	Thibault Raffaillac	116	Python 3	2023-07-29 23:39:48
8	Andrew He	118	Python 3	2016-08-12 18:49:33
9	Harry Zhang	119	Python 3	2022-12-21 19:43:55
10	Ahmed Chamseddine	121	Python 3	2023-09-14 11:39:16

#	User	Length	Language	Date
1	Thomas Feld	48	Ruby	2023-02-08 14:37:15
2	Frederik Spang	54	Ruby	2023-02-04 12:22:38
3	Andreas Severin Hauch Trøstrup	89	Ruby	2023-02-04 11:19:42
4	Frederik Petersen	116	Ruby	2023-02-03 15:37:19
5	Régis Hanol	129	Ruby	2022-01-13 16:20:37
6	Eugen Neagoe	145	Ruby	2023-06-13 15:53:28
7	Hidden user	146	Ruby	2020-06-07 14:18:45
8	Macdara mac an tSionnaigh	147	Ruby	2019-09-28 21:46:33
9	Hidden user	151	Ruby	2018-10-12 20:28:44
10	Hidden user	155	Ruby	2019-02-16 17:55:31

#	User	Length	Language	Date
1	Vincent Lagerros	212	Rust	2024-12-03 21:08:58
2	Emil Dichmann	441	Rust	2025-09-20 15:59:41
3	Andreas Giehm	482	Rust	2025-09-20 15:58:24
4	Malte Kildelund Rosenkilde	515	Rust	2025-02-04 10:08:13
5	Erik Funder Carstensen	578	Rust	2022-11-29 17:06:50
6	David Zacek	579	Rust	2021-06-02 00:37:38
7	Andreas Just Petersen	587	Rust	2023-01-31 15:01:27
8	Chaoyi Yin	596	Rust	2019-01-06 06:25:54
9	Robert Janczewski	603	Rust	2020-02-10 16:02:24
10	Kok Dith	642	Rust	2021-08-15 08:09:48

#	User	Length	Language	Date
1	Anton J Olsson	642	TypeScript	2023-08-06 17:18:53

#	User	Length	Language	Date
1	Joe Blower	1038	Zig	2025-05-23 03:07:34

Solution running time distribution