Codeforces Global Round 30 (Div. 1 + Div. 2)

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ContestId
Name
Phase
Frozen
Duration (Seconds)
Relative Time
Start Time
2164 Codeforces Global Round 30 (Div. 1 + Div. 2) FINISHED False 10800 13965923 Nov. 6, 2025, 2:35 p.m.

Problems

Solved
Index
Name
Type
Tags
Community Tag
Rating
( 202 ) G Pointless Machine PROGRAMMING interactive

This is an interactive problem. Madeline is playing with a pointless machine. The pointless machine has a hidden tree of size (n), and Madeline has to find the edges of the tree by asking the machine. In a query, Madeline will give the machine a permutation (p) of (1,2,\ldots,n), and the machine will return a sequence (q_1, q_2, \ldots, q_n), where (q_i) is the number of edges of the induced subgraph formed by the vertices (\{p_1,p_2,\ldots,p_i\}). Here, an induced subgraph of a graph (G(V,E)) formed by a subset of vertices (V' \subseteq V), is a graph consisting of vertices from this subset and all edges between vertices from subset that are present in original graph (G). However, the machine works slowly, so Madeline can only get the results at once after all queries are completed. The memory of this machine is not very large either, so Madeline can only ask (31) times. She doesn't know how to solve it, so she invited you to help her. Note that the interactor is non-adaptive . That is, tree is fixed in advance and doesn't change with your queries. Each test contains multiple test cases. The first line contains the number of test cases (t) ((1 \le t \le 10^4)). The description of the test cases follows. The only line of each test case contains a single integer (n) ((3\le n\le 5\cdot 10^4)) — the size of the tree. It is guaranteed that the sum of (n) over all test cases does not exceed (5\cdot 10^4). The interaction begins by reading the integer (n). Then, output a single integer (k) ((1 \leq k \leq 31)) — the number of queries. To ask a query, output a line in the following format: (p_{i,1}\,p_{i,2}\,\ldots\,p_{i,n}) ((1 \leq p_{i,j} \leq n), the (p_{i,j}) are distinct for each (i)) — a query described above. Once you've asked all (k) queries, read (k) lines of (n) integers (q_{i,j}) — the responses to the queries as described above. When you know

Tutorials

Codeforces Global Round 30 Editorial

Submissions

Submission Id
Author(s)
Index
Submitted
Verdict
Language
Test Set
Tests Passed
Time taken (ms)
Memory Consumed (bytes)
Tags
Rating
347829231 xvchongyv G Nov. 7, 2025, 5:42 a.m. OK C++17 (GCC 7-32) TESTS 34 1734 10035200
347782146 wthdouwant G Nov. 6, 2025, 6:29 p.m. OK C++17 (GCC 7-32) TESTS 34 1890 30617600
347765188 tourist G Nov. 6, 2025, 4:57 p.m. OK C++20 (GCC 13-64) TESTS 34 687 12800000
347828061 ORzyzRO G Nov. 7, 2025, 5:27 a.m. OK C++20 (GCC 13-64) TESTS 34 999 38092800
347804718 zltzlt G Nov. 6, 2025, 11:29 p.m. OK C++20 (GCC 13-64) TESTS 34 1343 14643200
347765820 strapple G Nov. 6, 2025, 4:59 p.m. OK C++20 (GCC 13-64) TESTS 34 1358 21708800
347781603 KroosTheKeenGlint G Nov. 6, 2025, 6:26 p.m. OK C++20 (GCC 13-64) TESTS 34 1453 55910400
347812277 xujindong G Nov. 7, 2025, 2:07 a.m. OK C++20 (GCC 13-64) TESTS 34 1811 19251200
347770009 StarSilk G Nov. 6, 2025, 5:12 p.m. OK C++20 (GCC 13-64) TESTS 34 1905 25702400
347764516 Otomachi_Una G Nov. 6, 2025, 4:55 p.m. OK C++20 (GCC 13-64) TESTS 34 1905 26316800
347785215 turmax G Nov. 6, 2025, 6:54 p.m. OK C++20 (GCC 13-64) TESTS 34 2780 56729600
347782800 turmax G Nov. 6, 2025, 6:34 p.m. OK C++20 (GCC 13-64) TESTS 34 2811 56729600
347798825 hungchi17 G Nov. 6, 2025, 9:24 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 468 10035200
347783113 Nachia G Nov. 6, 2025, 6:36 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 624 40652800
347768498 ksun48 G Nov. 6, 2025, 5:07 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 702 17100800
347803413 Adam_GS G Nov. 6, 2025, 10:56 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 859 20275200
347799089 rainboy G Nov. 6, 2025, 9:28 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 1265 12800000
347817688 XY_Eleven G Nov. 7, 2025, 3:11 a.m. OK C++23 (GCC 14-64, msys2) TESTS 34 1312 18739200
347772606 hos.lyric G Nov. 6, 2025, 5:20 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 1343 12595200
347769207 VivaciousAubergine G Nov. 6, 2025, 5:09 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 1858 43315200
347781832 maspy G Nov. 6, 2025, 6:27 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 2046 21504000
347782133 turmax G Nov. 6, 2025, 6:29 p.m. OK C++23 (GCC 14-64, msys2) TESTS 34 2999 56832000

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