42 lines
1.0 KiB
C++
42 lines
1.0 KiB
C++
#include "loops.hpp"
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#include <algorithm>
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#include <ranges>
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namespace control_flow {
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auto sum_range(const int from, const int to) -> int {
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return std::ranges::fold_left(
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std::views::iota(from, to + 1), // End-exclusive
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0,
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[](const int acc, const int x) { return acc + x; }
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);
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}
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auto factorial(const int n) -> long long
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pre(n >= 0)
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{
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if (n == 0 || n == 1) return 1;
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return std::ranges::fold_left(
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std::views::iota(2, n + 1), // End-exclusive
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1LL,
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[](const long long acc, const int x) { return acc * x; }
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);
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}
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auto count_occurrences(const std::vector<int>& data, const int target) -> int {
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int count = 0;
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std::ranges::for_each(data, [target, &count](const int x) {
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if (x == target) ++count;
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});
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return count;
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}
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auto first_index_of(const std::vector<int>& data, const int target) -> int {
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const auto it = std::ranges::find(data, target);
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if (it == data.end()) return -1;
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return static_cast<int>(std::distance(data.begin(), it));
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}
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} // namespace control_flow
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