Codeforces Round 972 (Div. 2) Editorial

Revision en85, by BiNARyBeastt, 2024-09-16 18:51:36

Thank you all for participating in the round.

All the problems were created by BiNARyBeastt during our classes in winter.

A — Simple Palindrome

Solution
Code

B1 — The Strict Teacher (Easy Version), B2 — The Strict Teacher (Hard Version)

Solution
Code

C — Lazy Narek

Solution
Code

D — Alter the GCD (Check this comment or the video editorial for an easier solution).

Solution
Code

E1 — Subtangle Game (Easy Version), E2 — Subtangle Game (Hard Version)

Solution
Code (E1)
Code (E2)

History

 
 
 
 
Revisions
 
 
  Rev. Lang. By When Δ Comment
en85 English BiNARyBeastt 2024-09-16 18:51:36 2
en84 English BiNARyBeastt 2024-09-16 18:50:59 2 Tiny change: 'oblem/D)\n\nCheck [t' -> 'oblem/D)\nCheck [t'
en83 English BiNARyBeastt 2024-09-16 18:50:28 2 Tiny change: 'lem/D)\n\n\nCheck ' -> 'lem/D)\n\nCheck '
en82 English BiNARyBeastt 2024-09-16 18:49:33 5 Tiny change: 'oblem/D)\nCheck [t' -> 'oblem/D)\n\n\nCheck [t' (published)
en81 English BiNARyBeastt 2024-09-16 18:48:58 127 (saved to drafts)
en80 English BiNARyBeastt 2024-09-16 18:43:40 38
en79 English BiNARyBeastt 2024-09-15 14:12:22 223
en78 English BiNARyBeastt 2024-09-15 12:51:31 3 Tiny change: ' if (n <= 20) { // sl' -> ' if (n <= 300) { // sl'
en77 English Tsovak 2024-09-15 11:45:51 0 (published)
en76 English Tsovak 2024-09-15 11:45:26 2 Tiny change: 'iminate $k $from the s' -> 'iminate $k$ from the s'
en75 English Tsovak 2024-09-15 11:43:42 4 (saved to drafts)
en74 English BiNARyBeastt 2024-09-15 11:35:54 5 Tiny change: 'ting from index +1 or even e' -> 'ting from $ind+1$ or even e'
en73 English BiNARyBeastt 2024-09-15 10:46:01 224
en72 English BiNARyBeastt 2024-09-15 10:42:59 161
en71 English Tsovak 2024-09-15 01:06:19 0 (published)
en70 English Tsovak 2024-09-15 01:05:40 224 Tiny change: 'y even $x$ $dp_{x,i,' -> 'y even $x$, $dp_{x,i,'
en69 English Tsovak 2024-09-15 00:53:34 1630
en68 English Tsovak 2024-09-15 00:51:28 1191 (saved to drafts)
en67 English Tsovak 2024-09-15 00:34:10 0 (published)
en66 English Tsovak 2024-09-15 00:33:49 1448
en65 English Tsovak 2024-09-15 00:33:17 1446
en64 English Tsovak 2024-09-15 00:31:58 13 Tiny change: 'oiler>\n\n~~~~~\n#' -> 'oiler>\n\n<spoiler summary="Code (E1)">\n~~~~~\n#'
en63 English Tsovak 2024-09-15 00:28:41 2 Tiny change: 'r summary=Hint 5">\n' -> 'r summary="Hint 5">\n'
en62 English Tsovak 2024-09-15 00:27:36 1242
en61 English Tsovak 2024-09-15 00:20:42 18
en60 English Tsovak 2024-09-15 00:12:09 2 Tiny change: 'pend on $a-1$. One of' -> 'pend on $a_1$. One of'
en59 English Tsovak 2024-09-15 00:08:45 1 Tiny change: 'Finalizing**\n\nBut ' -> 'Finalizing.**\n\nBut '
en58 English Tsovak 2024-09-15 00:08:16 6 Tiny change: '\approx O(\cdot 10^9)$. It' -> '\approx O(10^9)$. It'
en57 English Tsovak 2024-09-15 00:07:54 4 Tiny change: '\approx O(5\tcdot 10^8)$. It is ' -> '\approx O(\cdot 10^9)$. It is '
en56 English Tsovak 2024-09-15 00:05:42 5243
en55 English Tsovak 2024-09-14 23:36:39 5356 Tiny change: ' $\gcd$-s.\n\nLet's ' -> ' $\gcd$-s.**\n\nLet's ' (saved to drafts)
en54 English Tsovak 2024-09-14 20:28:37 0 (published)
en53 English Tsovak 2024-09-14 20:28:24 2 Tiny change: 'ty: $O(n*m*7)$.\n\n</s' -> 'ty: $O(n*m)$.\n\n</s' (saved to drafts)
en52 English Tsovak 2024-09-14 20:14:13 254
en51 English Tsovak 2024-09-14 20:07:44 0 (published)
en50 English Tsovak 2024-09-14 20:06:32 32 Tiny change: 'm*7)$.\n\nMemory complexity: $O(n*m*7)$.\n</spoile' -> 'm*7)$.\n\n</spoile'
en49 English Tsovak 2024-09-14 20:05:33 3053 (saved to drafts)
en48 English Tsovak 2024-09-14 19:44:05 0 (published)
en47 English Tsovak 2024-09-14 19:43:33 1 Tiny change: 'roblem/E1)\n[E2 &mda' -> 'roblem/E1),\n[E2 &mda'
en46 English Tsovak 2024-09-14 19:43:01 9373 Tiny change: 'the matrix.\n</spoile' -> 'the matrix?\n</spoile'
en45 English BiNARyBeastt 2024-09-14 19:12:15 4652
en44 English BiNARyBeastt 2024-09-14 19:07:26 2870 Reverted to en41
en43 English BiNARyBeastt 2024-09-14 19:04:03 2895
en42 English BiNARyBeastt 2024-09-14 18:58:54 4623
en41 English Tsovak 2024-09-13 21:49:10 288
en40 English Tsovak 2024-09-13 21:36:59 401 Tiny change: 't most $\leg(M)$). Al' -> 't most $\log(M)$). Al'
en39 English Tsovak 2024-09-13 21:19:34 934 Tiny change: 'ddle part. Then, we c' -> 'ddle part.\n\nThen, we c'
en38 English Tsovak 2024-09-13 21:03:58 112
en37 English Tsovak 2024-09-13 21:01:58 2 Tiny change: 'e exactly A, and that' -> 'e exactly $A$, and that'
en36 English Tsovak 2024-09-13 21:01:05 1523
en35 English Tsovak 2024-09-13 20:47:10 20
en34 English Tsovak 2024-09-13 20:37:22 83
en33 English Tsovak 2024-09-13 20:34:06 742 Tiny change: 'summary="HIint>\nLet'' -> 'summary="Hint>\nLet''
en32 English Tsovak 2024-09-13 19:59:19 163
en31 English Tsovak 2024-09-13 19:51:12 552 Tiny change: ' of $a$.\nLet's de' -> ' of $a$.\n\nLet's de'
en30 English Tsovak 2024-09-13 18:45:05 1383
en29 English Tsovak 2024-09-13 18:42:32 1153
en28 English Tsovak 2024-09-13 18:37:58 22
en27 English Tsovak 2024-09-13 18:15:53 243
en26 English Tsovak 2024-09-13 18:11:48 6
en25 English Tsovak 2024-09-13 18:10:32 87 Tiny change: ' + counted\textunderscorescore$.\n\' -> ' + counted \textunderscore score$.\n\'
en24 English Tsovak 2024-09-13 18:01:01 33 Tiny change: '-\infty$. We loop through the $n$ strings. For the ' -> '-\infty$. For the '
en23 English Tsovak 2024-09-13 17:59:35 148
en22 English Tsovak 2024-09-13 17:53:06 1657 Tiny change: ' = dp_4 = $\infty$. W' -> ' = dp_4 = \infty$. W'
en21 English Tsovak 2024-09-13 17:27:12 90
en20 English Tsovak 2024-09-13 17:25:54 214
en19 English Tsovak 2024-09-13 17:20:21 745 Tiny change: 'blem/B1)\n\n[B2 &mda' -> 'blem/B1)\n[B2 &mda'
en18 English Tsovak 2024-09-13 17:19:03 20
en17 English Tsovak 2024-09-12 21:32:15 18
en16 English Tsovak 2024-09-12 21:31:07 454
en15 English Tsovak 2024-09-12 21:22:15 41
en14 English Tsovak 2024-09-12 21:21:16 90 Tiny change: 'picked as a middle cell) of two t' -> 'picked as the middle) of two t'
en13 English Tsovak 2024-09-12 21:18:18 82
en12 English Tsovak 2024-09-12 21:17:19 1077 Tiny change: 'n\n[2005A &mdash; Simple Pa' -> 'n\n[2005A - Simple Pa'
en11 English Tsovak 2024-09-12 20:46:42 402
en10 English Tsovak 2024-09-12 20:41:59 2 Tiny change: 'ontest/2009/problem/A' -> 'ontest/2005/problem/A'
en9 English Tsovak 2024-09-12 20:41:29 632 Tiny change: 'oblem/A)\n<spoiler' -> 'oblem/A)\n\n<spoiler'
en8 English Tsovak 2024-09-12 20:22:14 671 Tiny change: ' 2^y > 2 \times 2^{y-1} \' -> ' 2^y > 2 \cdot 2^{y-1} \'
en7 English Tsovak 2024-09-12 19:54:08 1 Reverted to en5
en6 English BiNARyBeastt 2024-09-12 19:39:55 1 Tiny change: '\n\n<spoiler' -> '\n<spoiler'
en5 English Tsovak 2024-09-12 19:38:17 80 Tiny change: '\n<spoiler s' -> '<spoiler s'
en4 English Tsovak 2024-09-12 19:10:33 214 Tiny change: 'he problem.\n\n1. Let's say w' -> 'he problem:\n\n1. Firstly, let's say w'
en3 English Tsovak 2024-09-12 19:05:09 13 Tiny change: 'problem.\n1. Let'' -> 'problem.\n\n\n1. aaa\n2. bbb\n\n\n1. Let''
en2 English Tsovak 2024-09-12 19:03:33 6
en1 English Tsovak 2024-09-12 19:01:54 1293 Initial revision (saved to drafts)