#include <bits/stdc++.h>

typedef long long ll;

using namespace std;

struct cmp{
    bool operator()(pair<ll, ll> a, pair<ll, ll> b) const{
        if(a.first == b.first) return a.second < b.second;
        return a.first < b.first;
    }
};

int main(){

    ll n;
    cin >> n;
    set<pair<ll, ll>, cmp> s;
    s.insert(make_pair(0, 0));

    for(ll i = 0; i < n; i++){
        ll m;
        cin >> m;
        vector<pair<ll, ll>> crane(m);
        for(ll j = 0; j < m; j++){
            ll id, p;
            id++;
            cin >> id >> p;
            crane[j] = make_pair(id, p);
        }
        vector<ll> price(m + 1);
        auto find = s.lower_bound(make_pair(0, 0));
        price[0] = (*find).second;
        s.erase(find);
        for(ll j = 0; j < m; j++){
            auto find = s.lower_bound(make_pair(crane[j].first, LONG_LONG_MIN));
            if(find != s.end() && (*find).first == crane[j].first){
                price[j + 1] = (*find).second + crane[j].second;
                s.erase(find);
            }else price[j + 1] = LONG_LONG_MIN;
        }
        ll ma = LONG_LONG_MIN;
        for(ll j = 0; j < m + 1; j++){
            ma = max(ma, price[j]);
        }

        s.insert(make_pair(0, ma));
        for(ll j = 0; j < m; j++){
            s.insert(make_pair(crane[j].first, ma - crane[j].second));
        }
        
    }

    ll ma = LONG_LONG_MIN;
    for(auto x: s){
        ma = max(ma, x.second);
    }

    cout << ma << endl;

    return 0;
}