#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ordered_set tree<pair<pair<int, int>, int>, null_type, greater<pair<pair<int, int>, int> >, rb_tree_tag, tree_order_statistics_node_update>
using namespace std;
using namespace __gnu_pbds;
vector<pair<int, pair<int, int> > > beavers;
ordered_set set1, set2;
signed main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n, lastUpdated=0, ans=-1;
cin >> n;
for (int i=0; i<n; i++)
{
int x, y, z;
cin >> x >> y >> z;
beavers.push_back({x, {y, z}});
}
sort(beavers.begin(), beavers.end());
for (int i=1; i<n; i++)
{
if (beavers[i-1].first!=beavers[i].first)
{
for (int j=lastUpdated; j<i; j++)
{
int y=beavers[j].second.first, z=beavers[j].second.second;
pair<pair<int, int>, int> val1={{y, z}, j}, val2={{z, y}, j};
int rank1=set1.order_of_key(val1), rank2=set2.order_of_key(val2);
if (!set1.empty() && (*(--set1.end())).second!=(*(--set2.end())).second && rank1+2>set1.size() && rank2+2>set2.size())
continue;
if (rank1==rank2)
{
set1.insert(val1);
set2.insert(val2);
continue;
}
if (rank1<rank2)
{
if (rank1+2==set1.size())
{
int ind=(*(--set2.end())).second;
set1.erase({{beavers[ind].second.first, beavers[ind].second.second}, ind});
set2.erase({{beavers[ind].second.second, beavers[ind].second.first}, ind});
}
while (set1.size()>rank1+1)
{
int ind=(*(--set1.end())).second;
set1.erase({{beavers[ind].second.first, beavers[ind].second.second}, ind});
set2.erase({{beavers[ind].second.second, beavers[ind].second.first}, ind});
}
set1.insert(val1);
set2.insert(val2);
}
else
{
if (rank2+2==set1.size())
{
int ind=(*(--set1.end())).second;
set1.erase({{beavers[ind].second.first, beavers[ind].second.second}, ind});
set2.erase({{beavers[ind].second.second, beavers[ind].second.first}, ind});
}
while (set2.size()>rank2+1)
{
int ind=(*(--set2.end())).second;
set1.erase({{beavers[ind].second.first, beavers[ind].second.second}, ind});
set2.erase({{beavers[ind].second.second, beavers[ind].second.first}, ind});
}
set1.insert(val1);
set2.insert(val2);
}
}
lastUpdated=i;
}
if (set1.empty())
continue;
int ind1=(*(--set1.end())).second;
int ind2=(*(--set2.end())).second;
if (ind1!=ind2 && beavers[ind1].second.second>beavers[i].second.second && beavers[ind2].second.first>beavers[i].second.first)
ans=max(ans, beavers[i].first+beavers[ind1].second.second+beavers[ind2].second.first);
}
cout << ans;
}
