cpp-sets.cpp

// Sets-STL
// Learn about the set container. Given a problem with 3 queries, try to answer the queries using the set container.
// 
// https://www.hackerrank.com/challenges/cpp-sets/problem
// 

#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <set>
#include <algorithm>
using namespace std;


int main() {
 /* Enter your code here. Read input from STDIN. Print output to STDOUT */ 
 set<int> s;
 int q, op, i;
 
 cin >> q;
 while (q-- != 0)
 {
 cin >> op >> i;
 switch (op) {
 case 1: s.insert(i); break;
 case 2: s.erase(i); break;
 case 3: cout << (s.count(i) != 0 ? "Yes" : "No") << endl; 
 }
 }
 return 0;
}