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

#define ADD     1
#define DELETE  2
#define PRINT   3

int main() 
{
    
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */  
    int q {0} ;
    int y {0} ;
    int x {0} ;
    
    set<int> st ;
    
    set<int>::iterator itr = st.end() ;
    
    cin >> q ;
    
    for( int i = 0; i < q; i++ )
    {
        
        cin >> y ;
        cin >> x ;
        
        switch( y )
        {
            case ADD:
             
                st.insert( x ) ;
                
            break ;
            
            case DELETE:
                
                itr = st.find( x ) ;
                
                if( itr != st.end() )
                {
                    st.erase( x ) ;
                } 
                else
                {
                    
                }
                
            break ;
            
            case PRINT:
                
                itr = st.find( x ) ;
                
                if( itr != st.end() )
                {
                    cout << "Yes" << endl ;
                } 
                else
                {
                    cout << "No" << endl ;
                }
                
            break ;
            
            default: 
            
             // Do nothing.
            
            break ;
            
        }
        
    }
    
    return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main(){

    int p,q,r,x,i,k;
    set <int> st;
    cin>>k;

    for(i=0;i<k;i++){

    cin>>x;
    if(x==1){
        cin>>p;
        st.insert(p);
    }

    if(x==2){
        cin>>q;
        st.erase(q);
    }
    if(x==3){
        cin>>r;
        auto pos = st.find(r);
        if(pos!=st.end())
            cout<<"Yes\n";
        else
            cout<<"No\n";
    }

}

    printf("\n");
    return 0;
}