#include <bits/stdc++.h> using namespace std; #define int long long int dx[] = {1, -1, 0, 0}; int dy[] = {0, 0, 1, -1}; void solve(){ int n;cin>>n; int a[n+1],b[n+1]; vector<pair<int,int>> vt; for(int i=1;i<=n;i++){cin>>a[i]>>b[i];vt.push_back({a[i], b[i]});} sort(vt.begin(),vt.end()); int pref[n+1];pref[0]=0; for(int i=1;i<=n;i++)pref[i]=pref[i-1]+vt[i-1].second; int mn=LLONG_MAX;int ans=0; for(int i=1;i<=n;i++){mn=min(mn, pref[i-1]-vt[i-1].first); ans=max(ans, pref[i]-vt[i-1].first-mn);} cout<<ans<<"\n"; } signed main() { solve(); }