STL映射是否在插入时初始化基元类型？

#include<iostream>
#include <map>

int main() {
    std::map<int, float> my_map;

    // 插入一个新的键值对
    my_map[42] = 13.37f;

    // 输出映射中的值
    std::cout << "Value at key 42: " << my_map[42]<< std::endl;
    std::cout << "Value at key 0: " << my_map[0]<< std::endl;

    return 0;
}

Value at key 42: 13.37
Value at key 0: 0