lixi.cpp

#include<iostream>
#include<cstdlib>
#include<vector>
#include<algorithm>

#define long long long
#define nln '\n'

using namespace std;

bool cmp_pair(const pair<long, long> &a, const pair<long, long> &b)
{
    if (a.second > b.second)
        return 1;
    if (a.second < b.second)
        return 0;
    if (a.first > b.first)
        return 1;
    if (a.first < b.first)
        return 0;
    return 0;
}


int main()
{
    cin.tie(0)->sync_with_stdio(0);
    cout.tie(0)->sync_with_stdio(0);
    //freopen("lixi.inp", "r", stdin);
    long n;
    cin >> n;
    vector<pair<long, long>> a(n);
    for (auto &i : a)
        cin >> i.first >> i.second;
    // Process
    sort(a.begin(), a.end(), cmp_pair);
    long ans = 0, eng = 0;
    for (const auto &i : a){
        ans += i.first;
        eng += i.second-1;
        if (eng < 0)
            break;}
    cout << ans << nln;
    return 0;
}