使用迭代器通过元素数量而不是键从std::map获取子图

#include <iostream>
#include <map>

int main() {
    std::map<int, std::string> myMap;
    myMap[1] = "Apple";
    myMap[2] = "Banana";
    myMap[3] = "Orange";
    myMap[4] = "Grapes";
    myMap[5] = "Mango";

    int count = 3; // 要获取的元素数量
    int currentCount = 0;

    // 使用迭代器遍历map
    for (auto it = myMap.begin(); it != myMap.end() && currentCount < count; ++it) {
        std::cout << it->first << ": " << it->second << std::endl;
        currentCount++;
    }

    return 0;
}