#include <bits/stdc++.h>
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define F first
#define S second
using namespace std;
int N, A[150005], B[150005], C[150005];
vector<int> a, b, c;
signed main()
{
cin >> N;
for (int i = 1; i <= N; i++)
{
cin >> A[i] >> B[i] >> C[i];
a.emplace_back(i);
b.emplace_back(i);
c.emplace_back(i);
}
sort(a.begin(), a.end(), [&](int i, int j)
{ return A[i] < A[j]; });
sort(b.begin(), b.end(), [&](int i, int j)
{ return B[i] < B[j]; });
sort(c.begin(), c.end(), [&](int i, int j)
{ return C[i] < C[j]; });
while (!a.empty() && !b.empty() && !c.empty())
{
int i = a.back(), j = b.back(), k = c.back();
if (B[i] >= B[j] || C[i] >= C[k])
{
a.pop_back();
continue;
}
if (A[j] >= A[i] || C[j] >= C[k])
{
b.pop_back();
continue;
}
if (A[k] >= A[i] || B[k] >= B[j])
{
c.pop_back();
continue;
}
cout << A[i] + B[j] + C[k] << '\n';
return 0;
}
cout << -1 << '\n';
}
