C++ map遍历的几种方式_C++ map迭代器与C++11 range for循环

#include <map>
#include <iostream>
<p>std::map<int, std::string> myMap = {{1, "apple"}, {2, "banana"}, {3, "cherry"}};</p><p><span>立即学习</span>“<a href="https://pan.quark.cn/s/6e7abc4abb9f" style="text-decoration: underline !important; color: blue; font-weight: bolder;" rel="nofollow" target="_blank">C++免费学习笔记（深入）</a>”；</p><p>for (std::map<int, std::string>::iterator it = myMap.begin(); it != myMap.end(); ++it) {
std::cout << "Key: " << it->first << ", Value: " << it->second << std::endl;
}</p>

for (std::map<int, std::string>::const_iterator it = myMap.begin(); it != myMap.end(); ++it) {
    std::cout << "Key: " << it->first << ", Value: " << it->second << std::endl;
}

for (auto it = myMap.begin(); it != myMap.end(); ++it) {
    std::cout << "Key: " << it->first << ", Value: " << it->second << std::endl;
}

for (const auto& pair : myMap) {
    std::cout << "Key: " << pair.first << ", Value: " << pair.second << std::endl;
}

for (auto& pair : myMap) {
    pair.second += "_modified"; // 合法：修改 value
    // pair.first = 100; // 非法：key 是 const，不可修改
}

for (const auto& [key, value] : myMap) {
    std::cout << "Key: " << key << ", Value: " << value << std::endl;
}