std::flat_multimap<Key,T,Compare,KeyContainer,MappedContainer>:: keys
From zh.cppreference.net
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flat multimap
C++
Containers library
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(C++26)
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(C++11)
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(C++23)
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(C++23)
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(C++23)
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(C++23)
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(C++20)
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(C++23)
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std::flat_multimap
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const
key_container_type
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keys
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const
noexcept
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(C++23 起) | |
返回被适配键容器的常量引用。等价于 return c. keys ; 。
内容返回值底层键容器。 复杂度常量。 示例
运行此代码
#include <flat_map> #include <print> #include <type_traits> #include <vector> int main() { std::flat_multimap<int, double> adaptor{{1, 1.1}, {2, 2.2}, {3, 3.3}}; // 默认的键容器是 std::vector： static_assert(std::is_same_v<decltype(adaptor.keys()), const std::vector<int>&>); std::println("{}", adaptor.keys()); } 输出： [1, 2, 3] 参见
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