// // Created by ronal on 2/25/2023. // Problem Description Link. // https://www.hackerrank.com/challenges/cpp-sets/problem #include using namespace std; int main() { int Q, y, x; set S; cin >> Q; for(int i = 0; i < Q; i++){ cin >> y >> x; if(y == 1){ S.insert(x); }else if(y == 2){ S.erase(x); }else if(y == 3){ auto it = S.find(x); if(it != S.end()){ cout << "Yes\n"; }else{ cout << "No\n"; } } } return 0; }