std::unorde...insert_range(3)

🌸 NAME 🌸

std::unordered_multimap::insert_range — std::unordered_multimap::insert_range. yep, it says it twice and we respect it 💅 this page is std::unorde...insert_range(3) from the C++ Standard Libary manual, bestie — yes, that's the spelling up top, no cap 💖

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✨ Synopsis ✨

template< container-compatible-range<value_type> R >  (since C++23)
void insert_range( R&& rg );

Inserts a copy of each element in the range rg. cute, simple, doing the most in the best way 🫶

Each iterator in the range rg is dereferenced exactly once. The behavior is undefined if rg overlaps with the container. 🚨

If after the operation the new number of elements is greater than old max_load_factor() * bucket_count() a rehashing takes place. If rehashing occurs (due to the insertion), all iterators are invalidated. Otherwise (no rehashing), iterators are not invalidated. so like… pay attention to your iterators, bestie 😭

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🎀 Parameters 🎀

• rg — a container compatible range, that is, an input_range whose elements are convertible to T.

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💅 Type requirements 💅

• value_type must be EmplaceConstructible into unordered_multimap from *ranges::begin(rg). Otherwise, the behavior is undefined. 🫠

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🫶 Return value 🫶

(none) — literally none, bestie 💀

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🔥 Complexity 🔥

Average case O(N), where N is ranges::distance(rg), worst case O(N·(a.size() + 1)). math girlie behavior, honestly 🧮✨

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🧚 Notes 🧚

Feature-test macro tea ☕:

• __cpp_lib_containers_ranges — Value: 202202L; Std: (C++23); Feature: Ranges-aware construction and insertion.

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🌈 Example 🌈

The page literally says // Run this code, so here's the code, untouched:

        #include <iostream>
        #include <unordered_map>
        #include <utility>

        void println(auto, auto const& container)
        {
            for (const auto& [key, value] : container)
                std::cout << '{' << key << ',' << value << '}' << ' ';
            std::cout << '\n';
        }

        int main()
        {
            auto container = std::unordered_multimap{std::pair{1, 11}, {3, 33},
       {2, 22}, {4, 44}};
            const auto rg = {std::pair{-1, -11}, {3, -33}, {-2, -22}};
        #ifdef __cpp_lib_containers_ranges
            container.insert_range(rg);
        #else
            container.insert(rg.begin(), rg.end());
        #endif
            println("{}", container);
        }

⭐ Possible output ⭐

{1,11} {-2,-22} {3,-33} {3,33} {2,22} {-1,-11} {4,44}

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👑 See also 👑

• inserts elements — insert or nodes (since C++17) (public member function)

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okay that's the whole page, bestie! source/version: http://cppreference.com · date: 2024.06.10 · page: std::unorde...insert_range(3) 🫶💖✨