#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
namespace x = __gnu_pbds;
template <typename T>
using ordered_set = x::tree<T, x::null_type, less<T>, x::rb_tree_tag, x::tree_order_statistics_node_update>;
template <typename T>
using normal_queue = priority_queue<T, vector<T>, greater<>>;
#define all(x) begin(x), end(x)
#define sz(x) ((int) (x).size())
#define x first
#define y second
using ll = long long;
using ld = long double;
const int N = 1.6e5;
using P = array<int, 3>;
P a[N];
signed main() {
cin.tie(0)->sync_with_stdio(0);
int n;
cin >> n;
for (int i = 0; i < n; ++i) {
for (int j = 0; j < 3; ++j) {
cin >> a[i][j];
}
}
sort(a, a + n);
ll ans = -1;
for (int i = 1; i < n - 1; ++i) {
if (a[i][0] == a[i + 1][0]) {
continue;
}
// [0; i] and [i + 1; n - 1]
vector<P> f(a, a + i + 1), b(a, a + i + 1);
sort(all(f), [](const P &x, const P &y) {
return pair{x[1], x[2]} > pair{y[1], y[2]};
});
sort(all(b), [](const P &x, const P &y) {
return pair{x[2], x[1]} > pair{y[2], y[1]};
});
int y = -1, z = -1;
for (int j = 0; j <= i; ++j) {
if (f[j] != b[j]) {
y = f[j][1];
z = b[j][2];
break;
}
}
// cout << i << " " << y << " " << z << endl;
int x = -1;
for (int j = n - 1; j > i; --j) {
if (a[j][1] < y && a[j][2] < z) {
x = a[j][0];
break;
}
}
if (x != -1) {
ans = max(ans, 0ll + x + y + z);
}
}
cout << ans;
}
