// syntax for inserting elements in set using iterator range

s.insert(v.begin(), v.end());

for (int x : s) {
    cout << x << " ";
}
// Output: 10 20 30

return 0;

}

Yesterday, I participated in a real contest in my life, in July 11, 2024. Codeforces contests are very great, and fair also. I struggled a bit at first the time I'm new with this platform. After a while, I've been familiar with all the things in it. I hope more contests from Codeforces team, then I can boost my rating. Right now, I'm just a newbie.