#include <iostream>
#include <vector>
#include <set>
#include <map>
#include <algorithm>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <deque>
#include <cmath>
#include <array>
#include <random>
#include <cassert>

#define int long long

using namespace std;

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n;
    cin >> n;
    vector<pair<int, int>> a(n);
    for (int i = 0; i < n; i++) {
        cin >> a[i].first >> a[i].second;
    }
    sort(a.begin(), a.end(), [&] (pair<int, int> p1, pair<int, int> p2) {
        return p1.first > p2.first || (p1.first == p2.first && p1.second > p2.second);
    });
    set<pair<int, int>> q;
    int left = 0;
    int res = 0;
    for (int i = 0; i < n; i++) {
        if (left + (n - i - 1) >= a[i].first) {
            q.insert({a[i].second, i});
            continue;
        }
        res += a[i].second;
        left++;
    }
    cout << res;
}