#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using mint = atcoder::modint998244353;
// using mint = double;

#define rep(i, l, r) for (int i = (int)(l); i<(int)(r); i++)
#define ll long long
#define ld long double
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define siz(x) (int)(x).size()

template<class T> bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }

const int inf = 1e9;
const ll INF = 4e18;

template<class T> using pq = priority_queue<T, vector<T>, less<T>>;
template<class T> using spq = priority_queue<T, vector<T>, greater<T>>;

vector<int> di = {0, 0, 1, -1};
vector<int> dj = {1, -1, 0, 0};

struct Edge {
    int to, cost;
};

void solve() {
    int N; cin >> N;
    //dp[i][j] = 今iターン目で、iターン目も含めてこれからj回攻撃するときのmax
    ll A[N], B[N];
    rep(i, 0, N) cin >> B[i] >> A[i];
    vector dp(N+1, vector<ll>(N+1, -INF));
    dp[N][0] = 0;
    for (int i = N-1; i >= 0; i--) {
        rep(j, 0, N+1) {
            //攻撃する
            if (j > 0) {
                dp[i][j] = dp[i+1][j-1] + A[i];
            }
            chmax(dp[i][j], dp[i+1][j] + j * B[i]);
        }
    }
    ll ans = 0;
    rep(i, 0, N+1) chmax(ans, dp[0][i]);
    cout << ans << endl;
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    int T = 1;
    // cin >> T;
    while(T--) {
        solve();
    }
}