#include <bits/stdc++.h>
using i64 = long long;
#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) void(23)
#endif
int main() {
std::ios_base::sync_with_stdio(false);
std::cin.tie(nullptr);
int N;
std::cin >> N;
std::vector<std::array<int, 3>> A(N);
for (int i = 0; i < N; ++i) {
std::cin >> A[i][0] >> A[i][1] >> A[i][2];
}
std::vector<int> vx(N), vy(N), vz(N);
std::iota(vx.begin(), vx.end(), 0);
std::sort(vx.begin(), vx.end(), [&](auto lhs, auto rhs) -> int {
return A[lhs][0] > A[rhs][0];
});
std::iota(vy.begin(), vy.end(), 0);
std::sort(vy.begin(), vy.end(), [&](auto lhs, auto rhs) -> int {
return A[lhs][1] > A[rhs][1];
});
std::iota(vz.begin(), vz.end(), 0);
std::sort(vz.begin(), vz.end(), [&](auto lhs, auto rhs) -> int {
return A[lhs][2] > A[rhs][2];
});
std::vector<int> act(N, true);
int ans = -1;
int p0 = 0;
int p1 = 0;
int p2 = 0;
while (p0 < N && p1 < N && p2 < N) {
int a = vx[p0];
int b = vy[p1];
int c = vz[p2];
int cntx = (A[a][0] == A[a][0]) + (A[a][1] == A[b][1]) + (A[a][2] == A[c][2]);
int cnty = (A[b][0] == A[a][0]) + (A[b][1] == A[b][1]) + (A[b][2] == A[c][2]);
int cntz = (A[c][0] == A[a][0]) + (A[c][1] == A[b][1]) + (A[c][2] == A[c][2]);
if (!act[a]) {
p0++;
} else if (!act[b]) {
p1++;
} else if (!act[c]) {
p2++;
} else {
if (cntx > 1) {
act[a] = false;
p0++;
} else if (cnty > 1) {
act[b] = false;
p1++;
} else if (cntz > 1) {
act[c] = false;
p2++;
} else {
ans = A[a][0] + A[b][1] + A[c][2];
break;
}
}
}
std::cout << ans << '\n';
return 0;
}
