std::map<Key,T,Compare,Allocator>::insert

#include <iomanip>
#include <iostream>
#include <map>
#include <string>
 
using namespace std::literals;
 
template<typename It>
void printInsertionStatus(It it, bool success)
{
    std::cout << "Insertion of " << it->first << (success ? " succeeded\n" : " failed\n");
}
 
int main()
{
    std::map<std::string, float> karasunoPlayerHeights;
 
    // 重载 3 ：从右值引用插入
    const auto [it_hinata, success] = karasunoPlayerHeights.insert({"Hinata"s, 162.8});
    printInsertionStatus(it_hinata, success);
 
    {
        // 重载 1 ：从左值引用插入
        const auto [it, success2] = karasunoPlayerHeights.insert(*it_hinata);
        printInsertionStatus(it, success2);
    }
    {
        // 重载 2 ：经由转发到 emplace 插入
        const auto [it, success] = karasunoPlayerHeights.insert({"Kageyama", 180.6});
        printInsertionStatus(it, success);
    }
 
    {
        // 重载 6 ：带位置提示从右值引用插入
        const std::size_t n = std::size(karasunoPlayerHeights);
        const auto it = karasunoPlayerHeights.insert(it_hinata, {"Azumane"s, 184.7});
        printInsertionStatus(it, std::size(karasunoPlayerHeights) != n);
    }
    {
        // 重载 4 ：带位置提示从左值引用插入
        const std::size_t n = std::size(karasunoPlayerHeights);
        const auto it = karasunoPlayerHeights.insert(it_hinata, *it_hinata);
        printInsertionStatus(it, std::size(karasunoPlayerHeights) != n);
    }
    {
        // 重载 5 ：带位置提示经由转发到 emplace 插入
        const std::size_t n = std::size(karasunoPlayerHeights);
        const auto it = karasunoPlayerHeights.insert(it_hinata, {"Tsukishima", 188.3});
        printInsertionStatus(it, std::size(karasunoPlayerHeights) != n);
    }
 
    auto node_hinata = karasunoPlayerHeights.extract(it_hinata);
    std::map<std::string, float> playerHeights;
 
    // 重载 7 ：从范围插入
    playerHeights.insert(std::begin(karasunoPlayerHeights), std::end(karasunoPlayerHeights));
 
    // 重载 8 ：从 initializer_list 插入
    playerHeights.insert({{"Kozume"s, 169.2}, {"Kuroo", 187.7}});
 
 
    // 重载 9 ：插入结点
    const auto status = playerHeights.insert(std::move(node_hinata));
    printInsertionStatus(status.position, status.inserted);
 
    node_hinata = playerHeights.extract(status.position);
    {
        // 重载 10 ：插入结点带位置提示
        const std::size_t n = std::size(playerHeights);
        const auto it = playerHeights.insert(std::begin(playerHeights), std::move(node_hinata));
        printInsertionStatus(it, std::size(playerHeights) != n);
    }
 
 
    // 打印结果 map
    std::cout << std::left << '\n';
    for (const auto& [name, height] : playerHeights)
        std::cout << std::setw(10) << name << " | " << height << "cm\n";
}