poj3481

priority_queue如果想同时建立小根堆和大根堆需要这样写

priority_queue<Elem, vector<Elem> , greater<Elem> > pq3; //小根
priority_queue<Elem, vector<Elem> , less<Elem> > pq2;//大根

并重载大于和小于号

#include <iostream>
#include <cstdlib>
#include <cstring>
#include <cstdio>
#include <queue>
#include <vector>
using namespace std;

#define maxn 1000005

struct Elem
{
    int id, p;
    Elem()
    {
    }
    Elem(int ii, int pp) :
        id(ii), p(pp)
    {
    }
};

int vis[maxn];

priority_queue<Elem, vector<Elem> , greater<Elem> > pq3;
priority_queue<Elem, vector<Elem> , less<Elem> > pq2;

bool operator <(const Elem &a, const Elem &b)
{
    return a.p < b.p;
}

bool operator >(const Elem &a, const Elem &b)
{
    return a.p > b.p;
}

int main()
{
    //freopen("t.txt", "r", stdin);
    int x;
    memset(vis, -1, sizeof(vis));
    while (scanf("%d", &x), x)
    {
        if (x == 1)
        {
            int a, b;
            scanf("%d%d", &a, &b);
            vis[a] = b;
            pq2.push(Elem(a, b));
            pq3.push(Elem(a, b));
        }
        else if (x == 2)
        {
            Elem a;
            if (pq2.empty())
            {
                printf("0\n");
                continue;
            }
            do
            {
                a = pq2.top();
                pq2.pop();
            }while (!pq2.empty() && a.p != vis[a.id]);
            if (a.p == vis[a.id])
            {
                printf("%d\n", a.id);
                vis[a.id] = -1;
            }
            else
                printf("0\n");
        }
        else
        {
            Elem a;
            if (pq3.empty())
            {
                printf("0\n");
                continue;
            }
            do
            {
                a = pq3.top();
                pq3.pop();
            }while (!pq3.empty() && a.p != vis[a.id]);
            if (a.p == vis[a.id])
            {
                printf("%d\n", a.id);
                vis[a.id] = -1;
            }
            else
                printf("0\n");
        }
    }
    return 0;
}