#include <bits/stdc++.h> #define ll long long using namespace std; int main() { ios_base::sync_with_stdio(0); cin.tie(nullptr); int n; cin >> n; vector<pair<ll, ll>> v(n + 1); for (int i = 1; i <= n; i++) { cin >> v[i].first >> v[i].second; } sort(v.begin() + 1, v.end()); vector<ll> a(n + 1), b(n + 1, 0); for (int i = 1; i <= n; i++) { a[i] = v[i].first; b[i] = b[i - 1] + v[i].second; } ll mn = 1e18, ans = 0; for (int i = 1; i <= n; i++) { mn = min(mn, b[i - 1] - a[i]); ans = max(ans, b[i] - a[i] - mn); } cout << ans; }