#include <bits/stdc++.h>
using namespace std;

#define rep(i, l, r) for (int i = (int)(l); i<(int)(r); i++)
#define ll long long

int main() {
    int N; cin >> N;
    vector<tuple<char, ll, ll>> query(2*N);
    rep(i, 0, 2*N) {
        cin >> get<0>(query[i]) >> get<1>(query[i]) >> get<2>(query[i]);
    }
    int l = 0, r = 0;
    priority_queue<ll, vector<ll>, greater<ll>> Q;
    ll ans = 0;
    for (int i = 2*N-1; i >= 0; i--) {
        auto[c, L, R] = query[i];
        if (c == '(') l++;
        else r++;
        int m = min(l, r);
        ll p;
        if (c == '(') {
            //本来ならleft
            p = R - L;
            ans += L;
        }
        else {
            //本来ならright
            p = L - R;
            ans += R;
        }
        p = max(p, 0LL);
        Q.push(p);
        while((int)Q.size() > m) {
            Q.pop();
        }
    }
    while(!Q.empty()) {
        ll p = Q.top(); Q.pop();
        ans += p; 
    }
    cout << ans << endl;
}