Supermarket

#include <iostream>
#include <queue>
#include <cstdlib>
#include <iostream>
#include <algorithm>
using namespace std;
#define maxn 11115
struct node
{
    int profit,day;
} a[maxn];
bool cmp(node x,node y)
{
    return x.day>y.day;
}
int n,mxx,j,ans;
int main()
{
    while(cin>>n)
    {
        for(int i=0; i<n; i++)
            cin>>a[i].profit>>a[i].day;
        sort(a,a+n,cmp);
        priority_queue<int>q;
        mxx=a[0].day;
        j=ans=0;
        for(int big=mxx; big>0; big--)
        {
            for(; a[j].day>=big; j++)
                q.push(a[j].profit);
            if(!q.empty())
            {
                ans+=q.top();
                q.pop();
            }
        }
        cout<<ans<<endl;
    }
    return 0;
}