Good Bye 2025

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ContestId
Name
Phase
Frozen
Duration (Seconds)
Relative Time
Start Time
2178 Good Bye 2025 FINISHED False 10800 9559523 Dec. 27, 2025, 2:35 p.m.

Problems

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( 586 ) G deCH OR Dations PROGRAMMING data structures hashing

Due to supply chain issues in the North Pole (allegedly caused by a lazy elf), Santa is planning to give out hand-drawn circles as presents this Christmas. Please help him decorate them! There are (2n) equally spaced points around the circle, labeled (1,2,\ldots,2n) in clockwise order. Santa has chosen (n) chords with distinct endpoints, where chord (i) connects the points (a_i) and (b_i). He draws these chords onto the circle one by one, in order. After Santa has drawn the first (\ell) chords, consider any non-empty subset (S) of the (\ell) chords and let (1\leq c_1<c_2<\cdots<c_{|S|}\leq \ell) be their indices. (S) is defined to be a chain if and only if chord (c_k) intersects chord (c_{k+1}) for all (1\leq k < |S|). Note that (S) is always a chain if (|S|=1). Santa does not want any chord to be the odd one out. Therefore, he considers the chords to be tight-knit if and only if every chord appears in an even number of chains , taken over all chains that are subsets of the first (\ell) chords. For each (\ell) from (1) to (n), help Santa determine whether his chords are tight-knit . 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 first line of each test case contains a single integer (n) ((2\le n\le 5\cdot 10^5)) — the number of chords. Then (n) lines follow, the (i)-th line containing two integers (a_i) and (b_i) ((1\le a_i<b_i\le 2n)) — the endpoints of the (i)-th chord. It is guaranteed that all endpoints are distinct. It is guaranteed that the sum of (n) over all test cases does not exceed (5\cdot 10^5). For each test case, output a string of length (n) — the (\ell)-th character should be (1) if the first (\ell) chords are tight-knit and (0) otherwise. In the first test case, n

Tutorials

Submissions

Submission Id
Author(s)
Index
Submitted
Verdict
Language
Test Set
Tests Passed
Time taken (ms)
Memory Consumed (bytes)
Tags
Rating
355406542 Gold14526 G Dec. 27, 2025, 5:30 p.m. OK C++17 (GCC 7-32) TESTS 67 375 54272000
355432786 SDSXC G Dec. 28, 2025, 2:21 a.m. OK C++17 (GCC 7-32) TESTS 67 406 8089600
355428961 JaeminPark G Dec. 28, 2025, 12:46 a.m. OK C++17 (GCC 7-32) TESTS 67 406 33075200
355438247 cyx G Dec. 28, 2025, 4:11 a.m. OK C++17 (GCC 7-32) TESTS 67 421 16076800
355420390 al3xstr33t G Dec. 27, 2025, 8:55 p.m. OK C++17 (GCC 7-32) TESTS 67 437 32051200
355418821 BananaKatana G Dec. 27, 2025, 8:33 p.m. OK C++17 (GCC 7-32) TESTS 67 453 8601600
355399607 BINYU G Dec. 27, 2025, 5:10 p.m. OK C++17 (GCC 7-32) TESTS 67 453 18022400
355408549 mehtahet619_ G Dec. 27, 2025, 5:34 p.m. OK C++17 (GCC 7-32) TESTS 67 468 16691200
355402513 Auyyrwlj G Dec. 27, 2025, 5:19 p.m. OK C++17 (GCC 7-32) TESTS 67 468 40140800
355419800 Namnamseo G Dec. 27, 2025, 8:47 p.m. OK C++17 (GCC 7-32) TESTS 67 484 24064000
355444238 yangchang G Dec. 28, 2025, 5:43 a.m. OK C++20 (GCC 13-64) TESTS 67 296 8089600
355433825 WRKWRK G Dec. 28, 2025, 2:45 a.m. OK C++20 (GCC 13-64) TESTS 67 312 73216000
355426073 jeroenodb G Dec. 27, 2025, 11 p.m. OK C++20 (GCC 13-64) TESTS 67 343 13209600
355406195 Darren0724 G Dec. 27, 2025, 5:29 p.m. OK C++20 (GCC 13-64) TESTS 67 375 12185600
355439161 beaten_by_ai G Dec. 28, 2025, 4:27 a.m. OK C++20 (GCC 13-64) TESTS 67 390 16179200
355402443 Ivan_len G Dec. 27, 2025, 5:19 p.m. OK C++20 (GCC 13-64) TESTS 67 390 18124800
355428856 Chenly G Dec. 28, 2025, 12:42 a.m. OK C++20 (GCC 13-64) TESTS 67 390 20070400
355426104 kevinyang G Dec. 27, 2025, 11:01 p.m. OK C++20 (GCC 13-64) TESTS 67 390 24166400
355407628 Tobo G Dec. 27, 2025, 5:33 p.m. OK C++20 (GCC 13-64) TESTS 67 406 8089600
355399676 konb1 G Dec. 27, 2025, 5:10 p.m. OK C++20 (GCC 13-64) TESTS 67 406 18124800

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