如何在STL中使用unordered_set？

#include<iostream>
#include <unordered_set>

std::unordered_set<int> my_set;

my_set.insert(10);
my_set.insert(20);
my_set.insert(30);

if (my_set.find(20) != my_set.end()) {
    std::cout << "Element 20 found in the set."<< std::endl;
} else {
    std::cout << "Element 20 not found in the set."<< std::endl;
}

my_set.erase(10);

for (auto it = my_set.begin(); it != my_set.end(); ++it) {
    std::cout << "Element: " << *it<< std::endl;
}

#include<iostream>
#include <unordered_set>

int main() {
    std::unordered_set<int> my_set;

    my_set.insert(10);
    my_set.insert(20);
    my_set.insert(30);

    if (my_set.find(20) != my_set.end()) {
        std::cout << "Element 20 found in the set."<< std::endl;
    } else {
        std::cout << "Element 20 not found in the set."<< std::endl;
    }

    my_set.erase(10);

    for (auto it = my_set.begin(); it != my_set.end(); ++it) {
        std::cout << "Element: " << *it<< std::endl;
    }

    return 0;
}