#include<fstream>
using namespace std;
ifstream f("hashuri.in");
ofstream o("hashuri.out");
struct dat{
    int val,h,def;
    dat *dr,*st;
    dat(){
    val=0;
	h=def=0;
    dr=st=0;
    }
};
//typedef dat *lda;
int n;
dat *head;


dat *hight(dat *v){
	  if(v->dr!=0 && v->st!=0){
     	 v->h = max(v->dr->h,v->st->h)+1;
         v->def = v->dr->h - v->st->h;
     }else if(v->dr!=0 || v->st!=0){
     	if(v->dr!=0){
     		v->h = v->dr->h+1;
     		v->def = v->dr->h;
     	}else{
     		v->h = v->st->h+1;
     		v->def = -v->st->h;
     	}
     }else{
     	 v->h = 0;
         v->def = 0;
     }
     return v;
}
dat *rotleft(dat *v){
     dat *x = v->dr;
     v->dr = x->st;
     x->st = v;
     v = hight(v);
     x = hight(x);
    
     return x;
}
dat *rotright(dat *v){
     dat *x = v->st;
     v->st = x->dr;
     x->dr = v;
     v = hight(v);
     x = hight(x);
     return x;
}

dat *echilibru(dat *v){

 v = hight(v);
    
     
if(v->def==2){
    if(v->dr->def>=0)v = rotleft(v);
    else{
       v->dr = rotright(v->dr);
       v = rotleft(v);
    }
}
if(v->def==-2){
    if(v->st->def<=0)v = rotright(v);
    else {
           v->st = rotleft(v->st);
            v = rotright(v);
}

}
return v;
}
dat *adauga(dat *v, int x){
	
    if(v==0){
        dat *p = new dat;
        p->val = x;
        //v=p;
        return p;
    }
    
    if(v->val==x)return v;
    else if(v->val<x)v->st = adauga(v->st,x);
    else v->dr = adauga(v->dr,x);
    v = echilibru(v);
    return v;
}
int cautamax(dat *nod){
  if(nod->st==NULL)return nod->val;
  return cautamax(nod->st);
}
int cautamin(dat *nod){
  if(nod->dr==NULL)return nod->val;
  return cautamin(nod->dr);
}
int cauta(int x,dat *v){
	if(v==0)return 0;
		if(v->val == x)return 1;
	if(v->val<=x) return cauta(x,v->st);
	    else  return cauta(x,v->dr);
}
dat *sterge(int x,dat *v){
	 if(v==0)return 0;
		if(v->val == x){
			if(v->dr==0 && v->st==0){
				return 0;
			}else if(v->dr==0 || v->st==0){
				if(v->dr==0)return v->st;
				else return v->dr;
			}else{
				dat *p;
				for(p=v->dr;p->st!=0;p=p->st);
				 v->val = p->val;
			    v->dr =	 sterge(p->val,v->dr);
			    return echilibru(v);
			}
		}
		else
		if(v->val<x) v->st = sterge(x,v->st);
	    else  v->dr = sterge(x,v->dr);
	    
	    return echilibru(v);
}

int main(){
f>>n;
int x,y;
head=0;

for(int i=1;i<=n;i++){
    f>>x>>y;

    switch(x){
    	case 1:head = adauga(head,y);break;
    	case 2:head = sterge(y,head);break;
    	case 3:o<<cauta(y,head)<<"\n";break;
    }
}

}