如下所示，/(ㄒoㄒ)/~~

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cmath>
#include<set>
using namespace std;
int main()
{
	int n;int num;cin>>n;
	set<int> s1;int num1;int num2;
	set<int>::iterator it;
	set<int>::iterator it1;
	for(int i=0;i<n;i++)
	{
		scanf("%d%d",&num,&num1);
		if(num==1)
		{
			if(s1.insert(num1).second){}
			else printf("Already Exist\n");
		}
		else 
		{
			it=s1.end();
		    if(s1.empty()) printf("Empty\n");
			else if(s1.size()==1)
			{
				printf("%d\n",*s1.begin());
				s1.erase(*s1.begin());
			}
			else{
				  it1=--s1.lower_bound(*it);
				  it=s1.lower_bound(*it);
				  if(it==s1.end()){
				    printf("%d\n",*--it);
				    s1.erase(*it);
				  }
				  else if(it==s1.begin()){
				  printf("%d\n",*it);
				  s1.erase(*it);
			      }
			      else{
			      if(abs(num1-*it)<abs(num1-*it1)){
			      printf("%d\n",*it);
				  s1.erase(*it);
		 	      }
		 	      else{
		 	      printf("%d\n",*it1);
				  s1.erase(*it1);
		 	      }
			      }
			      it1=s1.end();
			      }
				}
			}
	return 0;
}