55 lines
973 B
C++
55 lines
973 B
C++
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// This file is part of the mcl project.
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// Copyright (c) 2022 merryhime
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// SPDX-License-Identifier: MIT
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#pragma once
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#include <bitset>
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#include "mcl/bitsizeof.hpp"
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#include "mcl/concepts/bit_integral.hpp"
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#include "mcl/stdint.hpp"
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namespace mcl::bit {
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template<BitIntegral T>
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inline size_t count_ones(T x) {
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return std::bitset<bitsizeof<T>>(x).count();
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}
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template<BitIntegral T>
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constexpr size_t count_leading_zeros(T x) {
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size_t result = bitsizeof<T>;
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while (x != 0) {
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x >>= 1;
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result--;
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}
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return result;
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}
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template<BitIntegral T>
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constexpr int highest_set_bit(T x) {
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int result = -1;
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while (x != 0) {
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x >>= 1;
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result++;
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}
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return result;
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}
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template<BitIntegral T>
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constexpr size_t lowest_set_bit(T x) {
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if (x == 0) {
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return bitsizeof<T>;
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}
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size_t result = 0;
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while ((x & 1) == 0) {
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x >>= 1;
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result++;
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}
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return result;
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}
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} // namespace mcl::bit
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