default order in set in c++

#include <iostream>
#include <set>

int main() {
    std::set<int> mySet;

    mySet.insert(30);
    mySet.insert(10);
    mySet.insert(40);
    mySet.insert(20);

    for (const auto& element : mySet) {
        std::cout << element << " ";
    }

    return 0;
}