#include <bits/stdc++.h>
#ifdef __LOCAL__
#include <debug_local.h>
#endif
using namespace std;
void testCase() {
int n;
cin >> n;
vector<tuple<int, int, int>> a(n);
for (auto &[x, y, z] : a) cin >> x >> y >> z;
sort(a.begin(), a.end());
set<pair<int, int>> s1, s2;
for (int i = 0; i < n; i++) {
auto [x, y, z] = a[i];
s1.insert({y, i});
s2.insert({z, i});
}
int ans = -1;
vector<bool> deleted(n);
while (!s1.empty() && (*s1.rbegin()).second == (*s2.rbegin()).second) {
deleted[(*s1.rbegin()).second];
s1.erase(prev(s1.end()));
s2.erase(prev(s2.end()));
}
for (int i = n - 1; i >= 0; i--) {
auto [x, y, z] = a[i];
if (deleted[i]) continue;
if (!s1.empty() && (*s1.rbegin()).second != i && (*s2.rbegin()).second != i) {
ans = max(ans, x + (*s1.rbegin()).first + (*s2.rbegin()).first);
}
s1.erase({y, i});
s2.erase({z, i});
deleted[i] = true;
while (!s1.empty() && (*s1.rbegin()).second == (*s2.rbegin()).second) {
deleted[(*s1.rbegin()).second];
s1.erase(prev(s1.end()));
s2.erase(prev(s2.end()));
}
}
cout << ans << "\n";
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
testCase();
}
