stau.space
My omnium-gatherom of scripts and source code.
1/* ========================================================================
2 *
3 * Filename:
4 * Description:
5 * Author:
6 * Version: 0.0.1
7 *
8 * ======================================================================== */
9#include <algorithm>
10#include <cmath>
11#include <cstdint>
12#include <iostream>
13#include <numeric>
14#include <ranges>
15#include <vector>
16
17#include <execution>
18#define PAR std::execution::par,
19
20using u32 = uint32_t;
21namespace ra = std::ranges;
22namespace vi = std::views;
23
24template <typename T> using ref = T&;
25
26auto print(ref<const std::vector<u32>> v) -> void;
27auto println(ref<const std::vector<u32>> v) -> void;
28
29auto decompose(u32 n) -> std::vector<u32>;
30
31auto is_cyclops(u32 n) -> bool;
32auto first_cyclops(size_t n) -> std::vector<u32>;
33
34auto is_disarium(u32 n) -> bool;
35auto first_disarium(size_t n) -> std::vector<u32>;
36
37auto main() -> int
38{
39 std::cout << std::boolalpha << is_disarium(1) << std::endl;
40 std::cout << std::boolalpha << is_disarium(2) << std::endl;
41 std::cout << std::boolalpha << is_disarium(3) << std::endl;
42 auto const k = first_disarium(18);
43 print(k);
44 return 0;
45}
46
47auto print(ref<const std::vector<u32>> v) -> void
48{
49 for (auto const& e : v)
50 std::cout << e << ' ';
51 std::cout << std::endl;
52}
53
54auto println(ref<const std::vector<u32>> v) -> void
55{
56 for (auto const& e : v)
57 std::cout << e << std::endl;
58}
59
60auto decompose(u32 n) -> std::vector<u32>
61{
62 auto v = std::vector<u32>(floor(log10(n)) + 1u, 0u);
63
64 for (auto& e : v | vi::reverse)
65 e = n % 10, n /= 10;
66
67 return v;
68}
69
70auto is_cyclops(u32 n) -> bool
71{
72 if (n == 0)
73 return true;
74 auto last_digit = n % 10;
75 auto ctr = 0;
76 while (last_digit != 0) {
77 ++ctr;
78 n /= 10;
79 last_digit = n % 10;
80 }
81 n /= 10;
82 last_digit = n % 10;
83 while (last_digit != 0) {
84 --ctr;
85 n /= 10;
86 last_digit = n % 10;
87 }
88 return n == 0 && ctr == 0;
89}
90
91auto first_cyclops(size_t n) -> std::vector<u32>
92{
93 auto v = std::vector(n, 0u);
94 auto ctr = 1;
95 for (auto& e : v) {
96 while (!is_cyclops(ctr))
97 ++ctr;
98 e = ctr;
99 ++ctr;
100 }
101
102 return v;
103}
104
105auto is_disarium(u32 n) -> bool
106{
107 auto const v = decompose(n);
108 auto ctr = 1u;
109
110 auto const transform = [&ctr](auto val) {
111 return std::pow(val, ctr++);
112 };
113
114 return std::transform_reduce(PAR v.cbegin(), v.cend(), 0L, std::plus{},
115 transform) == n;
116}
117
118auto first_disarium(size_t n) -> std::vector<u32>
119{
120 auto v = std::vector(n, 0u);
121 auto ctr = 1;
122 for (auto& e : v) {
123 while (!is_disarium(ctr))
124 ++ctr;
125 e = ctr;
126 ++ctr;
127 }
128 return v;
129}