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#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int mxsum(int **m, int n, int d, int visited[])
{
	int ans;
	int sel = -1;
	if (d == n)
		return 0;

	/* select the biggest of the line first */
	for (int i = 0; i < n; i++) {
		if (!visited[i]) {
			if (sel == -1)
				sel = i;
			else if (m[d][i] > m[d][sel])
				sel = i;
		}
	}
	visited[sel] = 1;
	ans = m[d][sel] + mxsum(m, n, d+1, visited);
	visited[sel] = 0;

	for (int i = 0; i < n; i++) {
		if (visited[i] || i == sel)
			continue;
		visited[i] = 1;
		int t = m[d][i];
		/* estimate the maximum value of remaining numbers */
		int re = 0;
		for (int j = d+1; j < n; j++) {
			int linemax = 0;
			for (int k = 0; k < n; k++) {
				if (!visited[k] && m[j][k] > linemax)
					linemax = m[j][k];
			}
			re += linemax;
		}
		if (t + re > ans) {
			t += mxsum(m, n, d+1, visited);
		}
		visited[i] = 0;
		if (t > ans)
			ans = t;
	}
	return ans;
}

int main()
{
	int n;
	int **m;
	int visited[15];

	scanf("%d", &n);
	m = (int**)malloc(sizeof(int*) * n);
	memset(visited, 0, sizeof(visited));
	for (int i = 0; i < n; i++) {
		m[i] = (int*)malloc(sizeof(int) * n);
		for (int j = 0; j < n; j++) {
			scanf("%d", &m[i][j]);
		}
	}

	printf("%d\n", mxsum(m, n, 0, visited));
}