#include <bits/stdc++.h>
#define int long long
#define pii pair<int, int>
#define vc vector
#define Fin(a) for (auto& i : a)
#define fih ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define mp(a, b) make_pair(a, b)
#define pb(a) push_back(a)
//#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("Ofast")
//#pragma GCC target("avx,avx2,fma")
using namespace std;
signed main() {
fih
int n;
cin >> n;
vc<pii> a(n);
Fin(a) {
cin >> i.first;
cin >> i.second;
}
sort(a.begin(), a.end());
deque<int> start(n);
deque<int> end(n);
for (int i = 0;i < n-1;i++) {
start[i+1] = a[i].second - (a[i+1].first - a[i].first) + start[i];
}
// start.push_back(0);
for (int i = n-1;i >= 1;i--) {
end[i-1] = a[i].second + (a[i-1].first - a[i].first) + end[i];
}
// end.push_front(0);
for (int i = 1;i <= n;i++) {
start[i] = min(start[i-1], start[i]);
}
for (int i = n-1;i >= 0;i--) {
end[i] = min(end[i], end[i+1]);
}
// Fin(start) cout << i << " ";
// cout << "\n";
// Fin(end) cout << i << " ";
// cout << "\n";
int sum = 0;
int min_ = 1000000000000000000;
int max_ = -1000000000000000000;
for (auto& i : a) {
sum += i.second;
min_ = min(min_, i.first);
max_ = max(max_, i.first);
}
sum -= (max_ - min_);
// cout << sum << "\n";
int v = 0;
for (int i = 0;i < n;i++) {
v = max(v, -(start[i] + end[i]));
}
cout << sum + v << "\n";
}
