#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")
#define ll long long
#define fori(i,j,k) for(ll i=j; i<=k;i++)
#define study ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define pb push_back
#define all(s) s.begin(),s.end()
#define ins insert
#define ss second
#define ff first
#ifndef DB
#define DB 0
#endif
#define debugl(l) if constexpr((l)<DB)
#define debug debugl(0)
const ll sz=1e6+10;
ll INF=1e18;
ll mod=1e9+7;
ll add=1e6;
bool comp(pair<ll,ll>a,pair<ll,ll>b){
return a.ss<b.ss;
}
void work(){
ll n;
cin>>n;
vector<pair<ll,ll>>v(n);
fori(i,0,n-1){
cin>>v[i].ff>>v[i].ss;
}
ll ans=(-INF);
fori(mask,1,(1<<n)-1){
ll cur=0;
ll maxi=0,mini=LLONG_MAX;
ll cnt=0;
fori(j,0,n-1){
if((1<<j)&mask){
cur+=v[j].ss;
cnt++;
maxi=max(maxi,v[j].ff);
mini=min(mini,v[j].ff);
}
}
if(cnt>1)
ans=max(ans,cur-maxi+mini);
}
cout<<ans;
}
int main()
{
//#ifndef LOCAL
// freopen("log1.txt","r",stdin);
// freopen("log2.txt","w",stdout);
//#endif
study;
ll t=1;
//cin>>t;
fori(i,1,t){
work();
}
}
