#include<iostream>

 #include<cstdio>

 #include<algorithm>

 #include<cstring>

 #define lc(x) ch[x][0]

 #define rc(x) ch[x][1]

 #define inf 0x3f3f3f3f

 #define N 200005

 using namespace std;

 int ch[N][];

 int k[N];int cnt,root;

 int size[N],fa[N];

 void push_up(int x)

 {

     size[x]=size[ch[x][]]+size[ch[x][]]+;

 }

 void rotate(int p)

 {

     int q=fa[p],y=fa[q],x=(p==ch[q][]);

     ch[q][x]=ch[p][x^];fa[ch[q][x]]=q;

     ch[p][x^]=q;fa[q]=p;

     fa[p]=y;

     if(y)

     {

         if(q==ch[y][])ch[y][]=p;

         else ch[y][]=p;

     }

     push_up(q);push_up(p);

     return ;

 }

 void splay(int x)

 {

     for(int y;y=fa[x];rotate(x))

     {

         if(fa[y])

         {

             if((ch[y][]==x&&ch[fa[y]][]==y)||(ch[y][]==x&&ch[fa[y]][]==y))rotate(y);

             else rotate(x);

         }

     }

     root=x;

 }

 int pre(int v)

 {

     int x=root;int tmp=-inf;

     while(ch[x][k[x]<v])

     {

         if(k[x]<v)tmp=k[x];

         x=ch[x][k[x]<v];

     }if(k[x]<v)tmp=k[x];

     return tmp;

 }

 int suc(int v)

 {

     int x=root;int tmp=inf;

     while(ch[x][k[x]<=v])

     {

         if(k[x]>v)tmp=k[x];

         x=ch[x][k[x]<=v];

     }if(k[x]>v)tmp=k[x];

     return tmp;

 }

 int find(int z)

 {

     int x=root;

     if(k[x]==z)return x;

     while(ch[x][k[x]<z])

     {

         x=ch[x][k[x]<z];

         if(k[x]==z)return x;

     }

     return ;

 }

 void insert(int z)

 {

     int x=root;size[x]++;

     while(ch[x][k[x]<z])x=ch[x][k[x]<z],size[x]++;

     cnt++;ch[x][k[x]<z]=cnt;k[cnt]=z;size[cnt]=;fa[cnt]=x;splay(cnt);

 }

 void del(int x)

 {

     splay(x);

     if(!ch[x][])

     {

         root=ch[x][];fa[ch[x][]]=;

     }

     else if(!ch[x][])

     {

         root=ch[x][];fa[ch[x][]]=;

     }

     else

     {

         fa[ch[x][]]=;int tmp=ch[x][];

         while(ch[tmp][])tmp=ch[tmp][];

         splay(tmp);ch[tmp][]=ch[x][];fa[ch[x][]]=tmp;

         push_up(tmp);

     }

     return ;

 }

 int fd(int kk,int x)

 {

     int l=ch[kk][];int r=ch[kk][];

     if(size[l]+==x)return k[kk];

     if(size[l]>=x)return fd(l,x);

     return fd(r,x-size[l]-);

 }

 int pr(int z)

 {

     int ans=;

     int x=root;

     while(x)

     {

         if(k[x]<=z)

         {

             ans+=size[ch[x][]]+;

             x=ch[x][];

         }

         else x=ch[x][];

     }

     return ans;

 }

 void yu()

 {

     root=;k[]=inf;cnt=;size[]=;

     insert(-inf);

 }

 int main()

 {

    yu();

    int n;

    scanf("%d",&n);

    for(int o=;o<=n;o++)

    {

          int t1,t2;

          scanf("%d%d",&t1,&t2);

          if(t1==)

          {

              insert(t2);

       }

       else if(t1==)

       {

           int x1=find(t2);

           if(x1!=)del(x1);

       }

       else if(t1==)

       {

           printf("%d\n",pr(t2-));

       }

       else if(t1==)

       {

            printf("%d\n",fd(root,t2+));

       }

       else if(t1==)

       {

            printf("%d\n",pre(t2));

       }

       else

       {

           printf("%d\n",suc(t2));

       }

    }

    return ;

 }