C++遍历map键值对的完整方法

#include <map>
#include <iostream>

int main() {
    std::map<std::string, int> scores = {
        {"Alice", 90},
        {"Bob", 85},
        {"Charlie", 95}
    };

    for (const auto& pair : scores) {
        std::cout << "Key: " << pair.first 
                  << ", Value: " << pair.second << std::endl;
    }
    return 0;
}

#include <map>
#include <iostream>

int main() {
    std::map<std::string, int> scores = {
        {"Alice", 90},
        {"Bob", 85},
        {"Charlie", 95}
    };

    for (std::map<std::string, int>::iterator it = scores.begin();
         it != scores.end(); ++it) {
        std::cout << "Key: " << it->first 
                  << ", Value: " << it->second << std::endl;
    }
    return 0;
}

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

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

for (auto it = scores.cbegin(); it != scores.cend(); ++it) {
    // 同上
}

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