Codeforces Round 976 (Div. 2) and Divide By Zero 9.0

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2020 Codeforces Round 976 (Div. 2) and Divide By Zero 9.0 FINISHED False 7200 48781523 Sept. 29, 2024, 3:35 p.m.

Problems

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( 264 ) F Count Leaves PROGRAMMING dp math number theory

Let (n) and (d) be positive integers. We build the the divisor tree (T_{n,d}) as follows: The root of the tree is a node marked with number (n). This is the (0)-th layer of the tree. For each (i) from (0) to (d - 1), for each vertex of the (i)-th layer, do the following. If the current vertex is marked with (x), create its children and mark them with all possible distinct divisors(^\dagger) of (x). These children will be in the ((i+1))-st layer. The vertices on the (d)-th layer are the leaves of the tree. For example, (T_{6,2}) (the divisor tree for (n = 6) and (d = 2)) looks like this: Define (f(n,d)) as the number of leaves in (T_{n,d}). Given integers (n), (k), and (d), please compute (\sum\limits_{i=1}^{n} f(i^k,d)), modulo (10^9+7). (^\dagger) In this problem, we say that an integer (y) is a divisor of (x) if (y \ge 1) and there exists an integer (z) such that (x = y \cdot z). 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 three integers (n), (k), and (d) ((1 \le n \le 10^9), (1 \le k,d \le 10^5)). It is guaranteed that the sum of (n) over all test cases does not exceed (10^9). For each test case, output (\sum\limits_{i=1}^{n} f(i^k,d)), modulo (10^9+7). In the first test case, (n = 6), (k = 1), and (d = 1). Thus, we need to find the total number of leaves in the divisor trees (T_{1,1}), (T_{2,1}), (T_{3,1}), (T_{4,1}), (T_{5,1}), (T_{6,1}). (T_{1,1}) has only one leaf, which is marked with (1). (T_{2,1}) has two leaves, marked with (1) and (2). (T_{3,1}) has two leaves, marked with (1) and (3). (T_{4,1}) has three leaves, marked with (1), (2), and (4). $$$T_

Tutorials

Tutorial for Codeforces Round 976 (Div. 2) and Divide By Zero 9.0

Submissions

Submission Id
Author(s)
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Submitted
Verdict
Language
Test Set
Tests Passed
Time taken (ms)
Memory Consumed (bytes)
Tags
Rating
283679723 neal F Sept. 29, 2024, 9:35 p.m. OK C++17 (GCC 7-32) TESTS 80 1827 61542400
283707888 copyPast77 F Sept. 30, 2024, 5:34 a.m. OK C++17 (GCC 7-32) TESTS 80 2562 82022400
283679180 lcyxds F Sept. 29, 2024, 9:26 p.m. OK C++17 (GCC 7-32) TESTS 80 3061 33280000
283680351 Sparkle_Twilight F Sept. 29, 2024, 9:46 p.m. OK C++17 (GCC 7-32) TESTS 80 3577 81203200
283677624 piyush_pransukhka F Sept. 29, 2024, 9:04 p.m. OK C++20 (GCC 13-64) TESTS 80 765 40550400
283693192 propane F Sept. 30, 2024, 2:31 a.m. OK C++20 (GCC 13-64) TESTS 80 874 111308800
283661196 Yoshinow2001 F Sept. 29, 2024, 6:42 p.m. OK C++20 (GCC 13-64) TESTS 79 905 31436800
283696131 propane F Sept. 30, 2024, 3:12 a.m. OK C++20 (GCC 13-64) TESTS 80 1108 111308800
283679719 neal F Sept. 29, 2024, 9:35 p.m. OK C++20 (GCC 13-64) TESTS 80 1233 61235200
283656899 G2Esports F Sept. 29, 2024, 5:34 p.m. OK C++20 (GCC 13-64) TESTS 79 1328 165990400
283681228 415411 F Sept. 29, 2024, 10:01 p.m. OK C++20 (GCC 13-64) TESTS 80 1530 36147200
283656890 zzpcd F Sept. 29, 2024, 5:34 p.m. OK C++20 (GCC 13-64) TESTS 79 1562 254259200
283679745 andreyDagger F Sept. 29, 2024, 9:35 p.m. OK C++20 (GCC 13-64) TESTS 80 1624 82636800
283707538 Lackofgod F Sept. 30, 2024, 5:31 a.m. OK C++20 (GCC 13-64) TESTS 80 1686 120320000
283673736 Be_dos F Sept. 29, 2024, 8:15 p.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1109 117862400
283667615 neal F Sept. 29, 2024, 7:18 p.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1171 61440000
283696702 kaixinw F Sept. 30, 2024, 3:20 a.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1234 128307200
283695555 RongYuzz F Sept. 30, 2024, 3:04 a.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1234 128307200
283707260 _MASSIMO_ F Sept. 30, 2024, 5:28 a.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1343 56627200
283678823 lcyxds F Sept. 29, 2024, 9:21 p.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1467 33484800
283679264 lcyxds F Sept. 29, 2024, 9:28 p.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1499 33075200
283679776 neal F Sept. 29, 2024, 9:36 p.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1562 59699200
283683306 ecnerwala F Sept. 29, 2024, 10:50 p.m. OK C++23 (GCC 14-64, msys2) TESTS 80 1905 27033600
283702352 ETO-leader F Sept. 30, 2024, 4:34 a.m. OK C++23 (GCC 14-64, msys2) TESTS 80 2046 257126400

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