#include <bits/stdc++.h>
#define int long long
const int MAXN = 101;
const int mod = 998244353;
struct Node
{
int x, y, z;
Node(int x, int y, int z) : x(x), y(y), z(z) {};
Node() = default;
int get_max()
{
return std::max(x, std::max(y, z));
}
};
signed
main()
{
std::ios::sync_with_stdio(false);
std::cin.tie(0);
int n;
std::cin >> n;
std::vector<Node> all(n);
std::multiset<int> x, y, z;
Node max = Node(0, 0, 0);
for (int i = 0; i < n; i++)
{
std::cin >> all[i].x >> all[i].y >> all[i].z;
x.insert(all[i].x);
y.insert(all[i].y);
z.insert(all[i].z);
}
std::map<std::pair<int, int>, std::vector<int>> nowxy, nowyz, nowxz;
std::vector<bool> used(n, false);
for (int i = 0; i < n; i++)
{
nowxy[std::make_pair(all[i].x, all[i].y)].push_back(i);
nowyz[std::make_pair(all[i].y, all[i].z)].push_back(i);
nowxz[std::make_pair(all[i].x, all[i].z)].push_back(i);
}
bool was = false;
max.x = *(--x.end());
max.y = *(--y.end());
max.z = *(--z.end());
do
{
was = false;
for (auto v : nowxy[std::make_pair(max.x, max.y)])
{
was = true;
if (!used[v])
{
x.erase(x.find(all[v].x));
z.erase(z.find(all[v].z));
y.erase(y.find(all[v].y));
}
used[v] = true;
// std::cout << v << ' ';
}
nowxy[std::make_pair(max.x, max.y)].clear();
for (auto v : nowxz[std::make_pair(max.x, max.z)])
{
was = true;
if (!used[v])
{
x.erase(x.find(all[v].x));
z.erase(z.find(all[v].z));
y.erase(y.find(all[v].y));
}
used[v] = true;
// std::cout << v << ' ';
}
nowxz[std::make_pair(max.x, max.z)].clear();
for (auto v : nowyz[std::make_pair(max.y, max.z)])
{
was = true;
if (!used[v])
{
x.erase(x.find(all[v].x));
z.erase(z.find(all[v].z));
y.erase(y.find(all[v].y));
}
used[v] = true;
// std::cout << v << ' ';
}
// std::cout << std::endl;
nowyz[std::make_pair(max.y, max.z)].clear();
if (x.size() == 0)
{
std::cout << -1;
return 0;
}
// std::cout << max.x << ' ' << max.y << ' ' << max.z << ' ' << was << std::endl;
max.x = *(--x.end());
max.y = *(--y.end());
max.z = *(--z.end());
} while (was);
std::cout << max.x + max.y + max.z;
}
