标准库头文件 <numeric>

 

C++

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标准库头文件

语言支持 <cfloat> <climits> <compare> (C++20) <contracts> (C++26) <coroutine> (C++20) <csetjmp> <csignal> <cstdarg> <cstddef> <cstdint> (C++11) <cstdlib> <exception> <initializer_list> (C++11)    <limits> <new> <source_location> (C++20) <stdfloat> (C++23) <typeinfo> <version> (C++20) 概念 <concepts> (C++20) 诊断 <cassert> <cerrno> <debugging> (C++26) <stacktrace> (C++23) <stdexcept> <system_error> (C++11) 内存管理 <memory> <memory_resource> (C++17) <scoped_allocator> (C++11) 元编程 <type_traits> (C++11) <ratio> (C++11)

通用工具 <any> (C++17) <bitset> <bit> (C++20) <charconv> (C++17) <expected> (C++23) <format> (C++20) <functional> <optional> (C++17) <tuple> (C++11) <typeindex> (C++11) <utility> <variant> (C++17) 容器 <array> (C++11) <deque> <flat_map> (C++23) <flat_set> (C++23) <forward_list> (C++11) <hive> (C++26) <inplace_vector> (C++26)    <list> <map> <mdspan> (C++23) <queue> <set> <span> (C++20) <stack> <unordered_map> (C++11) <unordered_set> (C++11) <vector> 迭代器 <iterator> 范围 <generator> (C++23) <ranges> (C++20)

算法 <algorithm> <numeric> 字符串 <cctype> <cstring> <cuchar> (C++11) <cwchar> <cwctype> <string_view> (C++17) <string> 文本处理 <clocale> <codecvt> (C++11/17/26*) <locale> <regex> (C++11) <text_encoding> (C++26)    数值 <cfenv> (C++11) <cmath> <complex> <linalg> (C++26) <numbers> (C++20) <random> (C++11) <simd> (C++26) <valarray> 时间 <chrono> (C++11) <ctime> C 兼容性 <ccomplex> (C++11/17/20*) <ciso646> (直到 C++20) <cstdalign> (C++11/17/20*) <cstdbool> (C++11/17/20*) <ctgmath> (C++11/17/20*)

输入/输出 <cinttypes> (C++11) <cstdio> <filesystem> (C++17) <fstream> <iomanip> <iosfwd> <iostream> <ios> <istream> <ostream> <print> (C++23) <spanstream> (C++23) <sstream> <streambuf> <strstream> (C++98/26*) <syncstream> (C++20) 并发支持 <atomic> (C++11) <barrier> (C++20) <condition_variable> (C++11) <future> (C++11) <hazard_pointer> (C++26) <latch> (C++20) <mutex> (C++11) <rcu> (C++26) <semaphore> (C++20) <shared_mutex> (C++14) <stdatomic.h> (C++23) <stop_token> (C++20) <thread> (C++11) 执行支持 <execution> (C++17)

 

此头文件是 numeric 库的一部分。

函数
iota (C++11)	用起始值的连续增量填充一个范围 (函数模板)
ranges::iota (C++23)	用起始值的连续增量填充一个范围 (算法函数对象)
accumulate	对元素范围求和或折叠 (函数模板)
reduce (C++17)	类似于 std::accumulate，但顺序不定 (函数模板)
transform_reduce (C++17)	应用一个可调用对象，然后以无序方式归约 (函数模板)
inner_product	计算两个元素范围的内积 (函数模板)
adjacent_difference	计算范围内相邻元素之间的差值 (函数模板)
partial_sum	计算元素范围的部分和 (函数模板)
inclusive_scan (C++17)	类似于 std::partial_sum，在第 ith 个和中包含第 ith 个输入元素 (函数模板)
exclusive_scan (C++17)	类似于 std::partial_sum，在第 ith 个和中排除第 ith 个输入元素 (函数模板)
transform_inclusive_scan (C++17)	应用一个可调用对象，然后计算包含扫描 (函数模板)
transform_exclusive_scan (C++17)	应用一个可调用对象，然后计算排除扫描 (函数模板)
gcd (C++17)	计算两个整数的最大公约数 (函数模板)
lcm (C++17)	计算两个整数的最小公倍数 (函数模板)
midpoint (C++20)	两个数字或指针之间的中点 (函数模板)
add_sat (C++26)	两个整数的饱和加法运算 (函数模板)
sub_sat (C++26)	两个整数的饱和减法运算 (函数模板)
mul_sat (C++26)	两个整数的饱和乘法运算 (函数模板)
div_sat (C++26)	两个整数的饱和除法运算 (函数模板)
saturate_cast (C++26)	返回一个整数值，该值被钳制到另一种整数类型的范围内 (函数模板)

概要

namespace std {
  // accumulate
  template<class InputIt, class T>
    constexpr T accumulate(InputIt first, InputIt last, T init);
  template<class InputIt, class T, class BinaryOperation>
    constexpr T accumulate(InputIt first, InputIt last, T init, BinaryOperation binary_op);
 
  // reduce
  template<class InputIt>
    constexpr typename iterator_traits<InputIt>::value_type
      reduce(InputIt first, InputIt last);
  template<class InputIt, class T>
    constexpr T reduce(InputIt first, InputIt last, T init);
  template<class InputIt, class T, class BinaryOperation>
    constexpr T reduce(InputIt first, InputIt last, T init, BinaryOperation binary_op);
  template<class ExecutionPolicy, class ForwardIt>
    typename iterator_traits<ForwardIt>::value_type
      reduce(ExecutionPolicy&& exec,
             ForwardIt first, ForwardIt last);
  template<class ExecutionPolicy, class ForwardIt, class T>
    T reduce(ExecutionPolicy&& exec,
             ForwardIt first, ForwardIt last, T init);
  template<class ExecutionPolicy, class ForwardIt, class T, class BinaryOperation>
    T reduce(ExecutionPolicy&& exec,
             ForwardIt first, ForwardIt last, T init, BinaryOperation binary_op);
 
  // inner product
  template<class InputIt1, class InputIt2, class T>
    constexpr T inner_product(InputIt1 first1, InputIt1 last1,
                              InputIt2 first2, T init);
  template<class InputIt1, class InputIt2, class T,
           class BinaryOperation1, class BinaryOperation2>
    constexpr T inner_product(InputIt1 first1, InputIt1 last1,
                              InputIt2 first2, T init,
                              BinaryOperation1 binary_op1,
                              BinaryOperation2 binary_op2);
 
  // transform reduce
  template<class InputIt1, class InputIt2, class T>
    constexpr T transform_reduce(InputIt1 first1, InputIt1 last1,
                                 InputIt2 first2,
                                 T init);
  template<class InputIt1, class InputIt2, class T,
           class BinaryOperation1, class BinaryOperation2>
    constexpr T transform_reduce(InputIt1 first1, InputIt1 last1,
                                 InputIt2 first2,
                                 T init,
                                 BinaryOperation1 binary_op1,
                                 BinaryOperation2 binary_op2);
  template<class InputIt, class T,
           class BinaryOperation, class UnaryOperation>
    constexpr T transform_reduce(InputIt first, InputIt last,
                                 T init,
                                 BinaryOperation binary_op, UnaryOperation unary_op);
  template<class ExecutionPolicy,
           class ForwardIt1, class ForwardIt2, class T>
    T transform_reduce(ExecutionPolicy&& exec,
                       ForwardIt1 first1, ForwardIt1 last1,
                       ForwardIt2 first2,
                       T init);
  template<class ExecutionPolicy,
           class ForwardIt1, class ForwardIt2, class T,
           class BinaryOperation1, class BinaryOperation2>
    T transform_reduce(ExecutionPolicy&& exec,
                       ForwardIt1 first1, ForwardIt1 last1,
                       ForwardIt2 first2,
                       T init,
                       BinaryOperation1 binary_op1,
                       BinaryOperation2 binary_op2);
  template<class ExecutionPolicy,
           class ForwardIt, class T,
           class BinaryOperation, class UnaryOperation>
    T transform_reduce(ExecutionPolicy&& exec,
                       ForwardIt first, ForwardIt last,
                       T init,
                       BinaryOperation binary_op, UnaryOperation unary_op);
 
  // partial sum
  template<class InputIt, class OutputIt>
    constexpr OutputIt partial_sum(InputIt first,
                                   InputIt last,
                                   OutputIt result);
  template<class InputIt, class OutputIt, class BinaryOperation>
    constexpr OutputIt partial_sum(InputIt first,
                                   InputIt last,
                                   OutputIt result,
                                   BinaryOperation binary_op);
 
  // exclusive scan
  template<class InputIt, class OutputIt, class T>
    constexpr OutputIt exclusive_scan(InputIt first, InputIt last,
                                      OutputIt result,
                                      T init);
  template<class InputIt, class OutputIt, class T, class BinaryOperation>
    constexpr OutputIt exclusive_scan(InputIt first, InputIt last,
                                      OutputIt result,
                                      T init, BinaryOperation binary_op);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class T>
    ForwardIt2 exclusive_scan(ExecutionPolicy&& exec,
                              ForwardIt1 first, ForwardIt1 last,
                              ForwardIt2 result,
                              T init);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2, class T,
           class BinaryOperation>
    ForwardIt2 exclusive_scan(ExecutionPolicy&& exec,
                              ForwardIt1 first, ForwardIt1 last,
                              ForwardIt2 result,
                              T init, BinaryOperation binary_op);
 
  // inclusive scan
  template<class InputIt, class OutputIt>
    constexpr OutputIt inclusive_scan(InputIt first, InputIt last, OutputIt result);
  template<class InputIt, class OutputIt, class BinaryOperation>
    constexpr OutputIt inclusive_scan(InputIt first, InputIt last,
                                      OutputIt result,
                                      BinaryOperation binary_op);
  template<class InputIt, class OutputIt, class BinaryOperation, class T>
    constexpr OutputIt inclusive_scan(InputIt first, InputIt last,
                                      OutputIt result,
                                      BinaryOperation binary_op, T init);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt2 inclusive_scan(ExecutionPolicy&& exec,
                              ForwardIt1 first, ForwardIt1 last,
                              ForwardIt2 result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class BinaryOperation>
    ForwardIt2 inclusive_scan(ExecutionPolicy&& exec,
                              ForwardIt1 first, ForwardIt1 last,
                              ForwardIt2 result,
                              BinaryOperation binary_op);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class BinaryOperation, class T>
    ForwardIt2 inclusive_scan(ExecutionPolicy&& exec,
                              ForwardIt1 first, ForwardIt1 last,
                              ForwardIt2 result,
                              BinaryOperation binary_op, T init);
 
  // transform exclusive scan
  template<class InputIt, class OutputIt, class T,
           class BinaryOperation, class UnaryOperation>
    constexpr OutputIt transform_exclusive_scan(InputIt first, InputIt last,
                                                OutputIt result,
                                                T init,
                                                BinaryOperation binary_op,
                                                UnaryOperation unary_op);
  template<class ExecutionPolicy,
           class ForwardIt1, class ForwardIt2, class T,
           class BinaryOperation, class UnaryOperation>
    ForwardIt2 transform_exclusive_scan(ExecutionPolicy&& exec,
                                        ForwardIt1 first, ForwardIt1 last,
                                        ForwardIt2 result,
                                        T init,
                                        BinaryOperation binary_op,
                                        UnaryOperation unary_op);
 
  // transform inclusive scan
  template<class InputIt, class OutputIt,
           class BinaryOperation, class UnaryOperation>
    constexpr OutputIt transform_inclusive_scan(InputIt first, InputIt last,
                                                OutputIt result,
                                                BinaryOperation binary_op,
                                                UnaryOperation unary_op);
  template<class InputIt, class OutputIt,
           class BinaryOperation, class UnaryOperation, class T>
    constexpr OutputIt transform_inclusive_scan(InputIt first, InputIt last,
                                                OutputIt result,
                                                BinaryOperation binary_op,
                                                UnaryOperation unary_op,
                                                T init);
  template<class ExecutionPolicy,
           class ForwardIt1, class ForwardIt2,
           class BinaryOperation, class UnaryOperation>
    ForwardIt2 transform_inclusive_scan(ExecutionPolicy&& exec,
                                        ForwardIt1 first, ForwardIt1 last,
                                        ForwardIt2 result,
                                        BinaryOperation binary_op,
                                        UnaryOperation unary_op);
  template<class ExecutionPolicy,
           class ForwardIt1, class ForwardIt2,
           class BinaryOperation, class UnaryOperation, class T>
    ForwardIt2 transform_inclusive_scan(ExecutionPolicy&& exec,
                                        ForwardIt1 first, ForwardIt1 last,
                                        ForwardIt2 result,
                                        BinaryOperation binary_op,
                                        UnaryOperation unary_op,
                                        T init);
 
  // adjacent difference
  template<class InputIt, class OutputIt>
    constexpr OutputIt adjacent_difference(InputIt first, InputIt last,
                                           OutputIt result);
  template<class InputIt, class OutputIt, class BinaryOperation>
    constexpr OutputIt adjacent_difference(InputIt first, InputIt last,
                                           OutputIt result,
                                           BinaryOperation binary_op);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2>
    ForwardIt2 adjacent_difference(ExecutionPolicy&& exec,
                                   ForwardIt1 first, ForwardIt1 last,
                                   ForwardIt2 result);
  template<class ExecutionPolicy, class ForwardIt1, class ForwardIt2,
           class BinaryOperation>
    ForwardIt2 adjacent_difference(ExecutionPolicy&& exec,
                                   ForwardIt1 first, ForwardIt1 last,
                                   ForwardIt2 result,
                                   BinaryOperation binary_op);
 
  // iota
  template<class ForwardIt, class T>
    constexpr void iota(ForwardIt first, ForwardIt last, T value);
 
  namespace ranges {
    template<class O, class T>
      using iota_result = out_value_result<O, T>;
 
    template<input_or_output_iterator O, sentinel_for<O> S, weakly_incrementable T>
      requires indirectly_writable<O, const T&>
      constexpr iota_result<O, T> iota(O first, S last, T value);
 
    template<weakly_incrementable T, output_range<const T&> R>
      constexpr iota_result<borrowed_iterator_t<R>, T> iota(R&& r, T value);
  }
 
  // greatest common divisor
  template<class M, class N>
    constexpr common_type_t<M, N> gcd(M m, N n);
 
  // least common multiple
  template<class M, class N>
    constexpr common_type_t<M, N> lcm(M m, N n);
 
  // midpoint
  template<class T>
    constexpr T midpoint(T a, T b) noexcept;
  template<class T>
    constexpr T* midpoint(T* a, T* b);
 
  // saturation arithmetic
  template<class T>
    constexpr T add_sat(T x, T y) noexcept;           // freestanding
  template<class T>
    constexpr T sub_sat(T x, T y) noexcept;           // freestanding
  template<class T>
    constexpr T mul_sat(T x, T y) noexcept;           // freestanding
  template<class T>
    constexpr T div_sat(T x, T y) noexcept;           // freestanding
  template<class T, class U>
    constexpr T saturate_cast(U x) noexcept;          // freestanding
}