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#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
struct node {
    ll l,r,key,val,cnt,siz;
} tr[100010];
ll n,idx,rt;
void pushup(ll p) {
    tr[p].siz=tr[tr[p].l].siz+tr[tr[p].r].siz+tr[p].cnt;
}
ll get_node(ll key) {
    tr[++idx].key=key;
    tr[idx].val=rand();
    tr[idx].cnt=tr[idx].siz=1;
    return idx;
}
void zig(ll &p) {
    ll q=tr[p].l;
    tr[p].l=tr[q].r,tr[q].r=p,p=q;
    pushup(tr[p].r),pushup(p);
}
void zag(ll &p) {
    ll q=tr[p].r;
    tr[p].r=tr[q].l,tr[q].l=p,p=q;
    pushup(tr[p].l),pushup(p);
}
void build() {
    get_node(-1e18),get_node(1e18);
    rt=1,tr[1].r=2;
    pushup(rt);
    if(tr[1].val<tr[2].val) zag(rt);
}
void insert(ll &p,ll key) {
    if(!p) p=get_node(key);
    else if(key==tr[p].key) ++tr[p].cnt;
    else if(key<tr[p].key) {
        insert(tr[p].l,key);
        if(tr[tr[p].l].val>tr[p].val) zig(p);
    } else {
        insert(tr[p].r,key);
        if(tr[tr[p].r].val>tr[p].val) zag(p);
    }
    pushup(p);
}
void remove(ll &p,ll key) {
    if(!p) return;
    if(key==tr[p].key) {
        if(tr[p].cnt>1) --tr[p].cnt;
        else if(tr[p].l || tr[p].r) {
            if(!tr[p].r || tr[tr[p].l].val>tr[tr[p].r].val) {
                zig(p);
                remove(tr[p].r,key);
            } else {
                zag(p);
                remove(tr[p].l,key);
            }
        } else p=0;
    } else if(key<tr[p].key) remove(tr[p].l,key);
    else remove(tr[p].r,key);
    pushup(p);
}
ll rnk(ll p,ll key) {
    if(key==tr[p].key) return tr[tr[p].l].siz+1;
    if(key<tr[p].key) return rnk(tr[p].l,key);
    return tr[tr[p].l].siz+tr[p].cnt+rnk(tr[p].r,key);
}
ll key(ll p,ll rnk) {
    if(rnk<=tr[tr[p].l].siz) return key(tr[p].l,rnk);
    if(rnk<=tr[tr[p].l].siz+tr[p].cnt) return tr[p].key;
    return key(tr[p].r,rnk-tr[tr[p].l].siz-tr[p].cnt);
}
ll pre(ll p,ll key) {
    if(!p) return -1e18;
    if(key<=tr[p].key) return pre(tr[p].l,key);
    return max(tr[p].key,pre(tr[p].r,key));
}
ll nxt(ll p,ll key) {
    if(!p) return 1e18;
    if(key>=tr[p].key) return nxt(tr[p].r,key);
    return min(tr[p].key,nxt(tr[p].l,key));
}
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin>>n;
    build();
    while(n--) {
        ll opt,x;
        cin>>opt>>x;
        if(opt==1) insert(rt,x);
        else if(opt==2) remove(rt,x);
        else if(opt==3) cout<<rnk(rt,x)-1<<"\n";
        else if(opt==4) cout<<key(rt,x+1)<<"\n";
        else if(opt==5) cout<<pre(rt,x)<<"\n";
        else cout<<nxt(rt,x)<<"\n";
    }
    return 0;
}