#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair <int,int>
#define f first
#define s second
const int N=5e5+5;
const int INF=1e16;
int n,ans=0,mx=0,mn=INF,sum=0,pos,tmp;
pii p[N]; // size , value
bool cmp(pii x,pii y){
if(abs(pos-x.f)!=abs(pos-y.f)) return abs(pos-x.f)<abs(pos-y.f);
else return x.s>y.s;
}
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cin >> n;
for(int i=1;i<=n;i++){
cin >> p[i].f >> p[i].s;
if(p[i].s>tmp) tmp=p[i].s,pos=p[i].f;
}
sort(p+1,p+1+n,cmp);
for(int i=1;i<=n;i++){
auto [a,b]=p[i];
mx=max(mx,a);
mn=min(mn,a);
sum+=b;
ans=max(ans,sum-(mx-mn));
}
cout << ans;
}
