#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 */

int Q;

std::cin>>Q;

std::set<int> s;

for(int i=0; i<Q; i++){

int y,x;

std::cin>>y>>x;

if(1 == y){

s.insert(x);

}

else if(2 == y){

s.erase(x);

}

else if(3 == y){

set<int>::iterator it = s.find(x);

if(it == s.end()){

std::cout<<"No"<<endl;

}

else{

std::cout<<"Yes"<<endl;

}

}

}

return 0;

}