1 #include <iostream>
2 #include <algorithm>
3 using namespace std;
4
5 int f[12][12][12][12], a[12][12], n, x, y, z;
6
7 int main() {
8 cin >> n >> x >> y >> z;
9 while (x != 0 || y != 0 || z != 0) {
10 a[x][y] = z;
11 cin >> x >> y >> z;
12 }
13
14 for (int i = 1; i <= n; ++i) {
15 for (int j = 1; j <= n; ++j) {
16 for (int k = 1; k <= n; ++k) {
17 for (int l = 1; l <= n; ++l) {
18
19 f[i][j][k][l] = max(max(f[i - 1][j][k - 1][l], f[i - 1][j][k][l - 1]), max(f[i][j - 1][k - 1][l], f[i][j - 1][k][l - 1])) + a[i][j] + a[k][l];
20 if (i == k && l == j) f[i][j][k][l] -= a[i][j];
21 }
22 }
23 }
24 }
25 cout << f[n][n][n][n] << endl;
26 return (0);
27 }