Solutions are presented as using the least memory and the fastest execution time. It also takes the top 10 most recent solutions from each language. If you want to limit to a specific index, click the "Solved" button and go to that problem.
ContestId |
Name |
Phase |
Frozen |
Duration (Seconds) |
Relative Time |
Start Time |
|---|---|---|---|---|---|---|
| 698 | Codeforces Round 363 (Div. 1) | FINISHED | False | 8100 | 307472123 | July 19, 2016, 1:05 p.m. |
Solved |
Index |
Name |
Type |
Tags |
Community Tag |
Rating |
|---|---|---|---|---|---|---|
| ( 6167 ) | B | Fix a Tree | PROGRAMMING | constructive algorithms dfs and similar dsu graphs trees | 1700 |
A tree is an undirected connected graph without cycles. Let's consider a rooted undirected tree with n vertices, numbered 1 through n . There are many ways to represent such a tree. One way is to create an array with n integers p 1 , p 2 , ..., p n , where p i denotes a parent of vertex i (here, for convenience a root is considered its own parent). Given a sequence p 1 , p 2 , ..., p n , one is able to restore a tree: There must be exactly one index r that p r = r . A vertex r is a root of the tree. For all other n - 1 vertices i , there is an edge between vertex i and vertex p i . A sequence p 1 , p 2 , ..., p n is called valid if the described procedure generates some (any) rooted tree. For example, for n = 3 sequences (1,2,2) , (2,3,1) and (2,1,3) are not valid. You are given a sequence a 1 , a 2 , ..., a n , not necessarily valid. Your task is to change the minimum number of elements, in order to get a valid sequence. Print the minimum number of changes and an example of a valid sequence after that number of changes. If there are many valid sequences achievable in the minimum number of changes, print any of them. The first line of the input contains an integer n ( 2 ≤ n ≤ 200 000 ) — the number of vertices in the tree. The second line contains n integers a 1 , a 2 , ..., a n ( 1 ≤ a i ≤ n ). In the first line print the minimum number of elements to change, in order to get a valid sequence. In the second line, print any valid sequence possible to get from ( a 1 , a 2 , ..., a n ) in the minimum number of changes. If there are many such sequences, any of them will be accepted. In the first sample, it's enough to change one element. In the provided output, a sequence represents a tree rooted in a vertex 4 (because p 4 = 4 ), which you can see on the left drawing below. One of other correct solutions would be a sequence 2 3 3 2 , representing a tree rooted in vertex 3 (right drawing below). On both drawings, roots are painted red. In the second sample, the |
| 46148 |
Submission Id |
Author(s) |
Index |
Submitted |
Verdict |
Language |
Test Set |
Tests Passed |
Time taken (ms) |
Memory Consumed (bytes) |
Tags |
Rating |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 19238149 | Gassa | B | July 19, 2016, 1:31 p.m. | OK | D | TESTS | 101 | 171 | 15564800 | 1700 | |
| 19909715 | Ahriman | B | Aug. 16, 2016, 2:50 p.m. | OK | FPC | TESTS | 101 | 390 | 5222400 | 1700 | |
| 34797924 | wmxwmx | B | Feb. 1, 2018, 10:02 a.m. | OK | FPC | TESTS | 101 | 405 | 5632000 | 1700 | |
| 19282874 | tieuchanlong | B | July 20, 2016, 2:39 p.m. | OK | FPC | TESTS | 101 | 420 | 3993600 | 1700 | |
| 19297266 | math4 | B | July 21, 2016, 8:21 a.m. | OK | FPC | TESTS | 101 | 436 | 3993600 | 1700 | |
| 19306394 | ez_ljh | B | July 21, 2016, 4:58 p.m. | OK | FPC | TESTS | 101 | 467 | 9011200 | 1700 | |
| 19370664 | Gray_58 | B | July 23, 2016, 6:50 p.m. | OK | FPC | TESTS | 101 | 468 | 3584000 | 1700 | |
| 19368962 | k2nt | B | July 23, 2016, 4:55 p.m. | OK | FPC | TESTS | 101 | 514 | 3174400 | 1700 | |
| 19368183 | LossABike | B | July 23, 2016, 3:57 p.m. | OK | FPC | TESTS | 101 | 546 | 3174400 | 1700 | |
| 19307803 | Noble_Mushtak | B | July 21, 2016, 6:32 p.m. | OK | GNU C | TESTS | 101 | 109 | 5324800 | 1700 | |
| 19244038 | Chipe1 | B | July 19, 2016, 1:59 p.m. | OK | GNU C | TESTS | 101 | 140 | 3174400 | 1700 | |
| 19284942 | double301 | B | July 20, 2016, 5:09 p.m. | OK | GNU C | TESTS | 101 | 156 | 18022400 | 1700 | |
| 20733138 | FHW_SO_WALL | B | Sept. 18, 2016, 11:57 a.m. | OK | GNU C++ | TESTS | 101 | 46 | 5529600 | 1700 | |
| 19238836 | TerryMcGinnis | B | July 19, 2016, 1:34 p.m. | OK | GNU C++ | TESTS | 101 | 61 | 17612800 | 1700 | |
| 30799708 | vjudge5 | B | Sept. 28, 2017, 9:05 a.m. | OK | GNU C++ | TESTS | 101 | 62 | 7987200 | 1700 | |
| 19267644 | GLK | B | July 20, 2016, 3:14 a.m. | OK | GNU C++ | TESTS | 101 | 77 | 1638400 | 1700 | |
| 19236631 | czllgzmzl | B | July 19, 2016, 1:25 p.m. | OK | GNU C++ | TESTS | 101 | 77 | 4198400 | 1700 | |
| 40481350 | Scut82 | B | July 17, 2018, 2:17 p.m. | OK | GNU C++ | TESTS | 101 | 78 | 2457600 | 1700 | |
| 19236048 | Lightning34 | B | July 19, 2016, 1:23 p.m. | OK | GNU C++ | TESTS | 101 | 78 | 2457600 | 1700 | |
| 36502158 | Worldwide_D | B | March 22, 2018, 12:39 p.m. | OK | GNU C++ | TESTS | 101 | 78 | 7372800 | 1700 | |
| 19265563 | Owaski | B | July 20, 2016, 1:14 a.m. | OK | GNU C++ | TESTS | 101 | 78 | 8396800 | 1700 | |
| 19235000 | jcvb | B | July 19, 2016, 1:19 p.m. | OK | GNU C++ | TESTS | 101 | 78 | 9011200 | 1700 | |
| 56683505 | rainboy | B | July 7, 2019, 8:12 p.m. | OK | GNU C11 | TESTS | 101 | 780 | 1843200 | 1700 | |
| 58246001 | luogu_bot3 | B | Aug. 4, 2019, 5:27 a.m. | OK | GNU C++11 | TESTS | 101 | 46 | 8806400 | 1700 | |
| 66669298 | hanyin11 | B | Dec. 12, 2019, 8:34 a.m. | OK | GNU C++11 | TESTS | 101 | 46 | 18432000 | 1700 | |
| 40186586 | hhhjhy | B | July 11, 2018, 2:14 a.m. | OK | GNU C++11 | TESTS | 101 | 61 | 7987200 | 1700 | |
| 40984044 | ReaLNero1 | B | July 30, 2018, 7:10 p.m. | OK | GNU C++11 | TESTS | 101 | 61 | 9625600 | 1700 | |
| 19441573 | babyfish | B | July 27, 2016, 12:22 p.m. | OK | GNU C++11 | TESTS | 101 | 77 | 2867200 | 1700 | |
| 28863898 | iamqzh | B | July 25, 2017, 3:16 a.m. | OK | GNU C++11 | TESTS | 101 | 77 | 7065600 | 1700 | |
| 19238422 | FizzyDavid | B | July 19, 2016, 1:33 p.m. | OK | GNU C++11 | TESTS | 101 | 77 | 11366400 | 1700 | |
| 19257545 | jomin | B | July 19, 2016, 5:01 p.m. | OK | GNU C++11 | TESTS | 101 | 78 | 1638400 | 1700 | |
| 19240252 | hzwer | B | July 19, 2016, 1:40 p.m. | OK | GNU C++11 | TESTS | 101 | 78 | 2867200 | 1700 | |
| 19240084 | FailedSystemTest | B | July 19, 2016, 1:40 p.m. | OK | GNU C++11 | TESTS | 101 | 78 | 3174400 | 1700 | |
| 45903171 | z2434445619 | B | Nov. 18, 2018, 6:43 a.m. | OK | GNU C++14 | TESTS | 101 | 77 | 2560000 | 1700 | |
| 49208562 | tokitsukaze | B | Jan. 30, 2019, 2:44 p.m. | OK | GNU C++14 | TESTS | 101 | 78 | 4300800 | 1700 | |
| 62596134 | qq574118090 | B | Oct. 15, 2019, 1:58 a.m. | OK | GNU C++14 | TESTS | 101 | 78 | 11264000 | 1700 | |
| 27252872 | Valiors | B | May 20, 2017, 8:20 p.m. | OK | GNU C++14 | TESTS | 101 | 93 | 1638400 | 1700 | |
| 27252918 | Valiors | B | May 20, 2017, 8:28 p.m. | OK | GNU C++14 | TESTS | 101 | 93 | 1638400 | 1700 | |
| 27293773 | Sereja | B | May 23, 2017, 4:08 a.m. | OK | GNU C++14 | TESTS | 101 | 93 | 1740800 | 1700 | |
| 30784630 | oToToT | B | Sept. 27, 2017, 5:17 p.m. | OK | GNU C++14 | TESTS | 101 | 93 | 2150400 | 1700 | |
| 25424806 | TooDifferent | B | March 12, 2017, 5:58 a.m. | OK | GNU C++14 | TESTS | 101 | 93 | 3481600 | 1700 | |
| 33851725 | SoSooding | B | Jan. 1, 2018, 5:10 p.m. | OK | GNU C++14 | TESTS | 101 | 93 | 3481600 | 1700 | |
| 26173368 | harshini1998 | B | April 6, 2017, 3:10 p.m. | OK | GNU C++14 | TESTS | 101 | 93 | 3481600 | 1700 | |
| 55417562 | abraham14 | B | June 11, 2019, 3:51 a.m. | OK | GNU C++17 | TESTS | 101 | 93 | 5836800 | 1700 | |
| 69562398 | noob2831 | B | Jan. 26, 2020, 11:07 a.m. | OK | GNU C++17 | TESTS | 101 | 108 | 1638400 | 1700 | |
| 65436829 | epcnhkapa | B | Nov. 20, 2019, 1:38 p.m. | OK | GNU C++17 | TESTS | 101 | 108 | 1638400 | 1700 | |
| 59227963 | PrvRage | B | Aug. 21, 2019, 2:25 p.m. | OK | GNU C++17 | TESTS | 101 | 109 | 1536000 | 1700 | |
| 52251166 | DomiKo | B | April 3, 2019, 12:30 a.m. | OK | GNU C++17 | TESTS | 101 | 109 | 1638400 | 1700 | |
| 58905432 | cvetoslav | B | Aug. 16, 2019, 10:55 a.m. | OK | GNU C++17 | TESTS | 101 | 109 | 1638400 | 1700 | |
| 57839559 | shenqihao | B | July 27, 2019, 8:48 a.m. | OK | GNU C++17 | TESTS | 101 | 109 | 1638400 | 1700 | |
| 50085901 | fishdog | B | Feb. 18, 2019, 7:24 a.m. | OK | GNU C++17 | TESTS | 101 | 109 | 1638400 | 1700 | |
| 50085404 | vjudge1 | B | Feb. 18, 2019, 7:09 a.m. | OK | GNU C++17 | TESTS | 101 | 109 | 1638400 | 1700 | |
| 50079200 | vjudge1 | B | Feb. 18, 2019, 2:11 a.m. | OK | GNU C++17 | TESTS | 101 | 109 | 1638400 | 1700 | |
| 19296913 | kuldeeppatel | B | July 21, 2016, 8:06 a.m. | OK | Java 7 | TESTS | 101 | 202 | 3072000 | 1700 | |
| 19238815 | PlayLikeNeverB4 | B | July 19, 2016, 1:34 p.m. | OK | Java 7 | TESTS | 101 | 202 | 8499200 | 1700 | |
| 19252949 | DukeOfYork | B | July 19, 2016, 2:57 p.m. | OK | Java 7 | TESTS | 101 | 233 | 0 | 1700 | |
| 19291790 | cs1235 | B | July 21, 2016, 3:28 a.m. | OK | Java 7 | TESTS | 101 | 249 | 4096000 | 1700 | |
| 63940175 | manish_98 | B | Oct. 31, 2019, 5:14 p.m. | OK | Java 8 | TESTS | 101 | 170 | 0 | 1700 | |
| 56683504 | Dukkha | B | July 7, 2019, 8:12 p.m. | OK | Java 8 | TESTS | 101 | 170 | 0 | 1700 | |
| 45424438 | ShowStopper728 | B | Nov. 7, 2018, 7:33 p.m. | OK | Java 8 | TESTS | 101 | 171 | 2764800 | 1700 | |
| 19238389 | piroz | B | July 19, 2016, 1:32 p.m. | OK | Java 8 | TESTS | 101 | 186 | 7884800 | 1700 | |
| 31497980 | __________ | B | Oct. 19, 2017, 5:11 a.m. | OK | Java 8 | TESTS | 101 | 187 | 20684800 | 1700 | |
| 19235416 | Egor | B | July 19, 2016, 1:21 p.m. | OK | Java 8 | TESTS | 101 | 202 | 0 | 1700 | |
| 19233722 | Petr | B | July 19, 2016, 1:15 p.m. | OK | Java 8 | TESTS | 101 | 202 | 2252800 | 1700 | |
| 53537247 | mennafadali | B | April 30, 2019, 3:36 a.m. | OK | Java 8 | TESTS | 101 | 202 | 3072000 | 1700 | |
| 19239359 | hama-du | B | July 19, 2016, 1:36 p.m. | OK | Java 8 | TESTS | 101 | 202 | 3276800 | 1700 | |
| 27310852 | V--o_o--V | B | May 23, 2017, 9:11 p.m. | OK | Java 8 | TESTS | 101 | 202 | 3481600 | 1700 | |
| 36753706 | vjudge4 | B | March 30, 2018, 4:41 p.m. | OK | Mono C# | TESTS | 101 | 545 | 32051200 | 1700 | |
| 36751358 | vjudge1 | B | March 30, 2018, 3:20 p.m. | OK | Mono C# | TESTS | 101 | 576 | 32051200 | 1700 | |
| 33250121 | chopik | B | Dec. 14, 2017, 8:23 p.m. | OK | Mono C# | TESTS | 101 | 655 | 55910400 | 1700 | |
| 22311196 | og.kostya | B | Nov. 18, 2016, 4:56 p.m. | OK | MS C# | TESTS | 101 | 109 | 7475200 | 1700 | |
| 19236731 | azukun | B | July 19, 2016, 1:26 p.m. | OK | MS C# | TESTS | 101 | 202 | 36044800 | 1700 | |
| 19240009 | haitao | B | July 19, 2016, 1:39 p.m. | OK | MS C# | TESTS | 101 | 249 | 27545600 | 1700 | |
| 59500859 | vjudge5 | B | Aug. 26, 2019, 2:41 a.m. | OK | MS C++ | TESTS | 101 | 93 | 1638400 | 1700 | |
| 19445473 | TonySnark | B | July 27, 2016, 4:31 p.m. | OK | MS C++ | TESTS | 101 | 93 | 3379200 | 1700 | |
| 50144136 | vjudge1 | B | Feb. 19, 2019, 2:04 a.m. | OK | MS C++ | TESTS | 101 | 93 | 4812800 | 1700 | |
| 19904011 | asdfadfavzxc | B | Aug. 16, 2016, 9:22 a.m. | OK | MS C++ | TESTS | 101 | 108 | 4505600 | 1700 | |
| 50095150 | vjudge2 | B | Feb. 18, 2019, 12:23 p.m. | OK | MS C++ | TESTS | 101 | 108 | 4812800 | 1700 | |
| 26318656 | Los_Angelos_Laycurse | B | April 12, 2017, 1:36 p.m. | OK | MS C++ | TESTS | 101 | 108 | 5529600 | 1700 | |
| 19239951 | waItz7I9 | B | July 19, 2016, 1:39 p.m. | OK | MS C++ | TESTS | 101 | 109 | 1638400 | 1700 | |
| 19352086 | hpuryc | B | July 23, 2016, 1:07 a.m. | OK | MS C++ | TESTS | 101 | 109 | 1843200 | 1700 | |
| 50086401 | vjudge1 | B | Feb. 18, 2019, 7:41 a.m. | OK | MS C++ | TESTS | 101 | 109 | 3993600 | 1700 | |
| 59527996 | vjudge4 | B | Aug. 26, 2019, 2:02 p.m. | OK | MS C++ | TESTS | 101 | 109 | 3993600 | 1700 | |
| 63662864 | CtrlAlt | B | Oct. 28, 2019, 2:22 p.m. | OK | MS C++ 2017 | TESTS | 101 | 296 | 3993600 | 1700 | |
| 57883237 | Kevinz1 | B | July 28, 2019, 8:44 a.m. | OK | MS C++ 2017 | TESTS | 101 | 311 | 3993600 | 1700 | |
| 52904101 | Yanhui | B | April 17, 2019, 12:06 p.m. | OK | MS C++ 2017 | TESTS | 101 | 311 | 3993600 | 1700 | |
| 19239133 | Giove | B | July 19, 2016, 1:35 p.m. | OK | PyPy 2 | TESTS | 101 | 1840 | 21708800 | 1700 | |
| 19720629 | vjudge2 | B | Aug. 8, 2016, 5:27 a.m. | OK | PyPy 3 | TESTS | 101 | 451 | 48025600 | 1700 | |
| 31210208 | dthung1602 | B | Oct. 11, 2017, 7:56 a.m. | OK | Python 2 | TESTS | 101 | 561 | 16691200 | 1700 | |
| 19778051 | tjsumonster | B | Aug. 11, 2016, 6:16 a.m. | OK | Python 2 | TESTS | 101 | 763 | 16691200 | 1700 | |
| 36753020 | diasdastan | B | March 30, 2018, 4:17 p.m. | OK | Python 3 | TESTS | 101 | 405 | 26521600 | 1700 | |
| 36753797 | vjudge3 | B | March 30, 2018, 4:44 p.m. | OK | Python 3 | TESTS | 101 | 405 | 26931200 | 1700 | |
| 36753536 | vjudge5 | B | March 30, 2018, 4:35 p.m. | OK | Python 3 | TESTS | 101 | 405 | 26931200 | 1700 | |
| 36751684 | vjudge5 | B | March 30, 2018, 3:32 p.m. | OK | Python 3 | TESTS | 101 | 420 | 26931200 | 1700 | |
| 42129034 | Mk_Python_v1 | B | Aug. 26, 2018, 5:11 p.m. | OK | Python 3 | TESTS | 101 | 451 | 19865600 | 1700 | |
| 59915396 | youness.amhaouch | B | Sept. 2, 2019, 6:57 p.m. | OK | Python 3 | TESTS | 101 | 857 | 15462400 | 1700 | |
| 26747571 | pedrofreire | B | April 29, 2017, 12:37 p.m. | OK | Python 3 | TESTS | 101 | 1200 | 28672000 | 1700 |
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