#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<ll> a(n), b(n); for (int i = 0; i < n; i++) { cin >> a[i] >> b[i]; } ll ans = 0; for (int mask = 0; mask < (1 << n); mask++) { ll mx = -1e18, mn = 1e18, sum = 0, d = 0; for (int i = 0; i < n; i++) { if (mask & (1 << i)) { d = 1; sum += b[i]; mn = min(mn, a[i]); mx = max(mx, a[i]); } } if (d) ans = max(ans, sum - (mx - mn)); } cout << ans << '\n'; }