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#include "ybwhead/ios.h"
const int maxn = 5e5 + 10;
struct fhq_treap
{
    struct node
    {
        int ch[2], val;
        unsigned int pri, siz;
    } p[maxn];
    int tot, root;
    void update(int x)
    {
        p[x].siz = p[p[x].ch[0]].siz + p[p[x].ch[1]].siz + 1;
    }
    int new_node(int v)
    {
        p[++tot].siz = 1;
        p[tot].val = v;
        p[tot].pri = rand() * rand();
        return tot;
    }
    int merge(int x, int y)
    {
        if (!x || !y)
            return x + y;
        if (p[x].pri < p[y].pri)
        {
            p[x].ch[1] = merge(p[x].ch[1], y);
            update(x);
            // cout << p[p[x].ch[1]].siz<<' '<<p[p[x]] << endl;
            return x;
        }
        else
        {
            p[y].ch[0] = merge(x, p[y].ch[0]);
            update(y);
            // cout << p[y].siz << endl;
            return y;
        }
    }
    void split(int now, int k, int &x, int &y)
    {
        if (!now)
        {
            x = y = 0;
            return;
        }
        if (p[now].val <= k)
            x = now, split(p[now].ch[1], k, p[now].ch[1], y);
        else
            y = now, split(p[now].ch[0], k, x, p[now].ch[0]);
        update(now);
    }
    int kth(int now, int k)
    {
        while (1)
        {
            if (k <= p[p[now].ch[0]].siz)
                now = p[now].ch[0];
            else if (k == p[p[now].ch[0]].siz + 1)
                return now;
            else
                k -= p[p[now].ch[0]].siz + 1, now = p[now].ch[1];
        }
    }
    void insert(int x)
    {
        int xx, yy;
        split(root, x, xx, yy);
        root = merge(merge(xx, new_node(x)), yy);
        // cout << p[root].siz << endl;
    }
    void erase(int x)
    {
        int xx, yy, zz;
        split(root, x, xx, yy);
        split(xx, x - 1, xx, zz);
        zz = merge(p[zz].ch[0], p[zz].ch[1]);
        root = merge(merge(xx, zz), yy);
    }
    int rank(int x)
    {
        int xx, yy;
        split(root, x - 1, xx, yy);
        int zz = p[xx].siz + 1;
        root = merge(xx, yy);
        return zz;
    }
    int kkth(int x)
    {
        // cout << root << endl;
        return p[kth(root, x)].val;
    }
    int lower(int x)
    {
        int xx, yy;
        // cout << x << endl;
        split(root, x - 1, xx, yy);
        // puts("1");
        // cout << kth(xx, p[xx].siz) << endl;
        int zz = p[kth(xx, p[xx].siz)].val;
        root = merge(xx, yy);
        return zz;
    }
    int upper(int x)
    {
        int xx, yy;
        split(root, x, xx, yy);
        int zz = p[kth(yy, 1)].val;
        // cout << kth(yy, 1) << endl;
        root = merge(xx, yy);
        return zz;
    }
} tr;
int n, m;
int main()
{
    yin >> m;
    while (m--)
    {
        int opt, x;
        yin >> opt >> x;
        if (opt == 1)
            tr.insert(x);
        if (opt == 2)
            tr.erase(x);
        if (opt == 3)
            yout << tr.rank(x) << endl;
        if (opt == 4)
            yout << tr.kkth(x) << endl;
        if (opt == 5)
            yout << tr.lower(x) << endl;
        if (opt == 6)
            yout << tr.upper(x) << endl;
    }
}