#include<bits/stdc++.h>

 using namespace std;

 typedef long long ll;

 const int maxn = ;

 const int INF = 1e9;

 inline void read(int &n) {

     register int x = , t = ;

     register char ch = getchar();

     while (ch != '-' && (ch<'' || ch>''))ch = getchar();

     if (ch == '-') { t = -; ch = getchar(); }

     while (ch >= ''&&ch <= '') { x = x *  + ch - ; ch = getchar(); }

     n = x * t;

 }

 int root, len;

 struct node {

     int fa;//节点的父节点

     int siz;//节点的子树数量

     int ch[];//节点的左(0)子节点和右(1)子节点

     int val;//节点的值

     int num;//节点的值的数量

 }a[maxn];

 inline void pushup(int x) {//更新当前节点的子树//当前子树的大小是左子树大小加上右子树大小当前当前节点个数

     a[x].siz = a[a[x].ch[]].siz + a[a[x].ch[]].siz + a[x].num;

 }

 inline void rotate(int x) {//旋转操作//将x旋转到x的父亲的位置

     int y = a[x].fa;//y是x的父节点

     int z = a[y].fa;//z是x的祖父节点

     int k = (a[y].ch[] == x);//求x是y的左(0)还是右(1)节点

     a[z].ch[a[z].ch[] == y] = x;//求y是z的左(0)还是右(1)节点，同时将x放在该位置

     a[x].fa = z;//修改x的父节点

     a[y].ch[k] = a[x].ch[k ^ ];//把x的儿子给y

     a[a[x].ch[k ^ ]].fa = y;//更新父节点为y

     a[x].ch[k ^ ] = y;//y变为x的子节点

     a[y].fa = x;//y的父亲更新为x

     pushup(y), pushup(x);//更新y和x的子节点数量

 }

 inline void splay(int x, int goal) {//将x旋转为goal的子节点

     while (a[x].fa != goal) {

         int y = a[x].fa;

         int z = a[y].fa;

         if (z != goal)

             (a[y].ch[] == x) ^ (a[z].ch[] == y) ? rotate(x) : rotate(y);

         //如果x和y同为左儿子或者右儿子先旋转y

         //如果x和y不同为左儿子或者右儿子先旋转x

         //如果不双旋的话，旋转完成之后树的结构不会变化

         rotate(x);

     }

     if (goal == )

         root = x;

 }

 inline void insert(int x) {

     int now = root, fa = ;//当前节点now和now的父节点fa

     while (now&&a[now].val != x) {//当now存在并且没有移动到当前的值

         fa = now;//父节点变为now

         now = a[now].ch[x > a[now].val];//x大于当前位置则now向右，否则now向左

     }

     if (now)//这个值出现过

         a[now].num++;//值增加

     else {//这个值第一次出现，要新建一个节点来存放

         now = ++len;

         if (fa)//父节点不是根节点(0)

             a[fa].ch[x > a[fa].val] = now;

         //初始化节点

         a[now].ch[] = a[now].ch[] = ;

         a[now].siz = ;

         a[now].num = ;

         a[now].fa = fa;

         a[now].val = x;

     }

     splay(now, );

 }

 inline void  Find(int x) {//查找x的位置，并将其旋转到根节点

     int now = root;

     if (!now)return;//数为空

     while (a[now].ch[x > a[now].val] && x != a[now].val)////当存在儿子并且当前位置的值不等于x

         now = a[now].ch[x > a[now].val];

     splay(now, );//把当前位置旋转到根节点

 }

 inline int Next(int x, int flag) {//查找x的前驱(0)或者后继(1)

     Find(x);

     int now = root;

     if (a[now].val > x&&flag)return now;//如果当前节点的值大于x并且要查找的是后继

     if (a[now].val < x && !flag)return now;//如果当前节点的值小于x并且要查找的是前驱

     now = a[now].ch[flag];//查找后继的话在右儿子上找，前驱在左儿子上找

     while (a[now].ch[flag ^ ])now = a[now].ch[flag ^ ];

     return now;

 }

 inline void Delete(int x) {//删除一个x

     int last = Next(x, );//查找x的前驱

     int next = Next(x, );//查找x的后继

     splay(last, ), splay(next, last);

     //将前驱旋转到根节点，后继旋转到根节点下面

     //很明显，此时后继是前驱的右儿子，x是后继的左儿子，并且x是叶子节点

     int now = a[next].ch[];//后继的左儿子，也就是x

     if (a[now].num > ) {//超过一个就删除一个

         a[now].num--;

         splay(now, );

     }

     else

         a[next].ch[] = ;//直接删除

 }

 inline int kth(int k) {//查找第k小的数

     int now = root;

     if (a[now].siz < k)

         return ;

     while () {

         int y = a[now].ch[];//y是左儿子

         if (k > a[y].siz + a[now].num) {//如果排名比左儿子的大小和当前节点的数量要大

             k -= a[y].siz + a[now].num;//排名减小

             now = a[now].ch[];//定在右儿子上找

         }

         else {

             if (k <= a[y].siz)

                 now = y;

             else

                 return a[now].val;

         }

     }

 }

 int main() {

     int n;

     read(n);

     root = , len = ;

     insert();

     insert(-);

     while (n--) {

         int q, x;

         read(q), read(x);

         if (q == )

             insert(x);

         else if (q == )

             Delete(x);

         else if (q == ) {

             Find(x);

             printf("%d\n", a[a[root].ch[]].siz);

         }

         else if (q == )

             printf("%d\n", kth(x + ));

         else if (q == )

             printf("%d\n", a[Next(x, )].val);

         else if (q == )

             printf("%d\n", a[Next(x, )].val);

     }

 }

 #include<bits/stdc++.h>

 using namespace std;

 typedef long long ll;

 const int maxn = 1e5 + ;

 int Siz[maxn], ls[maxn], rs[maxn], val[maxn], pos[maxn], root;

 int cnt;

 int send = ;

 inline int Rand() {

     send ^= send << ;

     send ^= send >> ;

     send ^= send << ;

     return send;

 }

 inline int New(int x) {

     cnt++;

     pos[cnt] = Rand();

     Siz[cnt] = ;

     val[cnt] = x;

     return cnt;

 }

 inline void up(int x) {

     Siz[x] = Siz[ls[x]] + Siz[rs[x]] + ;

 }

 void split_size(int x, int siz, int &A, int &B) {

     if (x == )return (void)(A = B = );

     if (siz <= Siz[ls[x]])

         B = x, split_size(ls[x], siz, A, ls[x]);

     else

         A = x, split_size(rs[x], siz - Siz[ls[x]] - , rs[x], B);

     up(x);

 }

 void split_val(int x, int v, int &A, int &B) {

     if (x == )return (void)(A = B = );

     if (v < val[x])

         B = x, split_val(ls[x], v, A, ls[x]);

     else

         A = x, split_val(rs[x], v, rs[x], B);

     up(x);

 }

 int Merge(int A, int B) {

     if (A ==  || B == )return A | B;

     int ans;

     if (pos[A] > pos[B])ans = A, rs[A] = Merge(rs[A], B);

     else ans = B, ls[B] = Merge(A, ls[B]);

     up(ans);

     return ans;

 }

 void dfs(int x) {

     if (x == )

         return;

     printf("%d ", x);

     dfs(ls[x]);

     dfs(rs[x]);

 }

 void insert(int x) {

     int A, B;

     split_val(root, x - , A, B);

     root = Merge(Merge(A, New(x)), B);

 }

 void Delete(int x) {

     int A, B, C, D;

     split_val(root, x - , A, B);

     split_size(B, , C, D);//C就是删除的节点

     root = Merge(A, D);

 }

 int Rank(int x) {//查x的排名

     int A, B, ans;

     split_val(root, x - , A, B);

     ans = Siz[A] + ;

     root = Merge(A, B);

     return ans;

 }

 int getR(int x) {//查第x名是什么

     int A, B, C, D, ans;

     split_size(root, x - , A, B);

     split_size(B, , C, D);

     ans = val[C];

     Merge(Merge(A, C), D);

     return ans;

 }

 int last(int x) {

     int A, B, C, D, ans;

     split_val(root, x - , A, B);

     split_size(A, Siz[A] - , C, D);

     ans = val[D];

     Merge(Merge(C, D), B);

     return ans;

 }

 int Next(int x) {

     int A, B, C, D, Ans;

     split_val(root, x, A, B);

     split_size(B, , C, D);

     Ans = val[C];

     root = Merge(Merge(A, C), D);

     return Ans;

 }

 int main() {

     int n;

     scanf("%d", &n);

     while (n--) {

         int opt, x;

         scanf("%d%d", &opt, &x);

         if (opt == )

             insert(x);

         else if (opt == )

             Delete(x);

         else if (opt == )

             printf("%d\n", Rank(x));

         else if (opt == )

             printf("%d\n", getR(x));

         else if (opt == )

             printf("%d\n", last(x));

         else if (opt == )

             printf("%d\n", Next(x));

     }

     return ;

 }