题目传送门😄

#include<cstdio>
#include<iostream>
#include<cmath>
#include<algorithm>
#include<set>
using namespace std;
int read(){
    int x = 0,f = 1;
    char c = getchar();
    while (c<'0'||c>'9') {
        if (c=='-') {
            f = -1;
        }
        c = getchar();
    }
    while (c>='0'&&c<='9') {
        x = x*10+c-'0';
        c = getchar();
    }
    return x*f;
}
multiset<int>q;
int n,t,x,order;

int main()
{
    q.insert(-0x7fffffff);
    q.insert(0x7fffffff);
    n = read();
    while(n--)
    {
        t = read();
        x = read();
        if(t==1)
        {
            multiset<int>::iterator it=q.lower_bound(x);

            order=0;

            for(multiset<int>::iterator i=q.begin();i!=it;i++,order++);

            printf("%d\n",order);
        }
        else if(t==2)
        {
            order=-1;

            for(multiset<int>::iterator it=q.begin();it!=q.end();it++)
            {
                order++;
                if(order==x)
                    printf("%d\n",*it);
            }
        }
        else if(t==3)
        {
            multiset<int>::iterator it=q.lower_bound(x);
            printf("%d\n",*(--it));
        }
        else if(t==4)
        {
            printf("%d\n",*q.upper_bound(x));
        }
        else
        {
            q.insert(x);
        }
    }
    return 0;
}

#include<cstdio>
#include<iostream>
#include<cmath>
#include<algorithm>
#include<set>
using namespace std;
int read(){
    int x = 0,f = 1;
    char c = getchar();
    while (c<'0'||c>'9') {
        if (c=='-') {
            f = -1;
        }
        c = getchar();
    }
    while (c>='0'&&c<='9') {
        x = x*10+c-'0';
        c = getchar();
    }
    return x*f;
}
multiset<int>q;
int n,t,x,order;

int main()
{
    q.insert(-0x7fffffff);
    q.insert(0x7fffffff);
    n = read();
    while(n--)
    {
        t = read();
        x = read();
        if(t==1)
        {
            multiset<int>::iterator it=q.lower_bound(x);

            order=0;

            for(multiset<int>::iterator i=q.begin();i!=it;i++,order++);

            printf("%d\n",order);
        }
        else if(t==2)
        {
            order=-1;

            for(multiset<int>::iterator it=q.begin();it!=q.end();it++)
            {
                order++;
                if(order==x)
                    printf("%d\n",*it);
            }
        }
        else if(t==3)
        {
            multiset<int>::iterator it=q.lower_bound(x);
            printf("%d\n",*(--it));
        }
        else if(t==4)
        {
            printf("%d\n",*q.upper_bound(x));
        }
        else
        {
            q.insert(x);
        }
    }
    return 0;
}