# BZOJ 3224 - 用Treap实现名次树

// BZOJ 3224, Treap + Kth

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cstdlib>
using namespace std;

struct Node {
Node *son[2]; // 0 <=> left, 1 <=> right
int p, v, s;
int cmp(int x) {
if (v==x) return -1;
return x<v ? 0 : 1;
}
void maintain() { s = son[1]->s + son[0]->s +1; }
} *root;

Node *null = new Node();

void init() {
null->s = 0;
root = null;
}

void rotate(Node *&o, int d) {
Node *k = o->son[d^1];
o->son[d^1] = k->son[d];
k->son[d] = o;
o->maintain();
k->maintain();
o = k;
}

// Movement 1
void insert(Node *&o, int x) {
if (o==null) {
o = new Node();
o->v = x;
o->son[0] = o->son[1] = null;
o->p = rand();
}
else {
int d = (x < o->v ? 0 : 1); // 也可以直接用cmp函数，但后面要写得麻烦一点
insert(o->son[d], x);
if (o->son[d]->p > o->p) rotate(o, d^1);
}
o->maintain();
}

// Movement 2
void remove(Node *&o, int x) {
if (o==null) return;
int d = o->cmp(x);
if (d==-1) {
Node *u = o;
if (o->son[0] != null && o->son[1] != null) {
int d2 = (o->son[0]->p > o->son[1]->p ? 1 : 0);
rotate(o, d2);
remove(o->son[d2], x);
}
else {
if (o->son[0] == null) o = o->son[1]; else o = o->son[0];
delete u;
}
} else remove(o->son[d], x);
if (o!=null) o->maintain();
}

// Movement 3
int get_rank(Node *o, int x) {
if (o == null) return 1;
if (x <= o->v) return get_rank(o->son[0], x);
return get_rank(o->son[1], x) + (o->son[0] == null ? 0 : o->son[0]->s) + 1;
}

// Movement 4
int kth(Node *o, int k) {
if (o==null || k<=0 || k > o->s) return 0; // 鲁棒语句：没有第k大的元素
int s = o->son[0]->s;
if (k==s+1) return o->v;
else if (k<=s) return kth(o->son[0], k);
else return kth(o->son[1], k-s-1);
}

// Movement 5
int query_pre(int x) {  // 注意求前驱或后继时要忽略相同元素
Node *t = root;
int ret=0;
while (t != null) {
if (t->v < x) {
ret = t->v;
t = t->son[1];
} else t = t->son[0];
}
return ret;
}

// Movement 6
int query_suf(int x) {
Node *t = root;
int ret=0;
while (t != null) {
if (t->v > x) {
ret = t->v;
t = t->son[0];
} else t = t->son[1];
}
return ret;
}

int main()
{
int m, op, x;
init();
while (m--) {