68 lines
1.8 KiB
C++
68 lines
1.8 KiB
C++
//
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// Created by Matthew Gretton-Dann on 03/12/2021.
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//
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#include <array>
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#include <cassert>
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#include <cctype>
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#include <iostream>
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#include <string>
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struct Triangle
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{
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Triangle() = default;
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Triangle(std::uint64_t l0, std::uint64_t l1, std::uint64_t l2) : lengths_({l0, l1, l2}) {}
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explicit Triangle(std::string const& s)
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{
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std::size_t idx{0};
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for (unsigned i = 0; i < 3; ++i) {
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while (idx < s.size() && std::isspace(s[idx]) != 0) {
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++idx;
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}
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assert(idx < s.size());
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std::size_t end{0};
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lengths_.at(i) = std::stoul(s.substr(idx), &end);
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idx += end;
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}
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}
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[[nodiscard]] auto is_valid() const -> bool
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{
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return (lengths_[0] + lengths_[1]) > lengths_[2] && (lengths_[0] + lengths_[2]) > lengths_[1] &&
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(lengths_[1] + lengths_[2]) > lengths_[0];
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}
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[[nodiscard]] auto length(unsigned side) const -> std::uint64_t { return lengths_.at(side); }
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void length(unsigned side, std::uint64_t length) { lengths_.at(side) = length; }
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private:
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std::array<std::uint64_t, 3> lengths_{0, 0, 0};
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};
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auto main() -> int
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{
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unsigned valid{0};
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std::string line;
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while (true) {
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std::array<Triangle, 3> triangles;
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for (unsigned i = 0; i < 3; ++i) {
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if (!std::getline(std::cin, line)) {
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std::cout << "Number of valid triangles: " << valid << '\n';
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return 0;
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}
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triangles.at(i) = Triangle{line};
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}
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std::array<Triangle, 3> transposed{
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Triangle{triangles[0].length(0), triangles[1].length(0), triangles[2].length(0)},
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Triangle{triangles[0].length(1), triangles[1].length(1), triangles[2].length(1)},
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Triangle{triangles[0].length(2), triangles[1].length(2), triangles[2].length(2)},
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};
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for (unsigned i = 0; i < 3; ++i) {
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if (transposed.at(i).is_valid()) {
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++valid;
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}
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}
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}
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}
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