#ifdef testing
#include <cassert>
#include <cstdio>
#include <vector>
#include <iostream>
#else
#include "soccer.h"
#endif //testing
using namespace std;
#define foru(i,a,b) for(int i = (a); i <= (b); ++i)
#define ford(i,a,b) for(int i = (a); i >= (b); --i)
const int MaxN = 2e3 + 5;
int n;
int a[MaxN][MaxN];
int l[MaxN][MaxN], sum[MaxN][MaxN], nxt[MaxN][MaxN], ans[MaxN][MaxN];
int get(int u, int v, int val, int arr[MaxN][MaxN]) {
int &x = nxt[u][v];
return arr[x][v] > val ? x = get(x, v, val, arr) : x;
}
int sol() {
int res = 0;
foru(i, 1, n)
foru(j, 1, n) l[i][j] = (a[i][j] ? 0 : l[i][j - 1] + 1);
foru(i, 1, n) foru(j, 1, n) ans[i][j] = 0;
foru(i, 1, n) foru(j, 1, n) sum[i][j] = 0;
foru(i, 1, n) {
foru(j, 1, n) if (a[i][j] == 0) {
nxt[i][j] = i - 1;
int prv = get(i, j, l[i][j], l);
sum[i][j] = sum[prv][j] + l[i][j] * (i - prv);
ans[i][j] += sum[i][j];
}
}
foru(i, 1, n) foru(j, 1, n) sum[i][j] = 0;
ford(i, n, 1) {
foru(j, 1, n) if (a[i][j] == 0) {
nxt[i][j] = i + 1;
int prv = get(i, j, l[i][j], l);
sum[i][j] = sum[prv][j] + l[i][j] * -(i - prv);
ans[i][j] += sum[i][j];
}
}
foru(i, 1, n) foru(j, 1, n)
ans[i][j] -= l[i][j];
foru(i, 1, n) foru(j, 1, n) if (a[i][j] == 0)
res = max(res, ans[i][j]);
return res;
}
int temp[MaxN][MaxN];
int biggest_stadium(int N, std::vector<std::vector<int>> F)
{
n = N;
foru(i, 0, n + 1) foru(j, 0, n + 1) a[i][j] = 1;
foru(i, 1, n) foru(j, 1, n)
a[i][j] = F[i - 1][j - 1];
int ans = 0;
ans = max(ans, sol());
// rotation
foru(i, 1, n) foru(j, 1, n) temp[i][j] = a[i][j];
foru(i, 1, n) foru(j, 1, n) a[n - j + 1][i] = temp[i][j];
ans = max(ans, sol());
// rotation
foru(i, 1, n) foru(j, 1, n) temp[i][j] = a[i][j];
foru(i, 1, n) foru(j, 1, n) a[n - j + 1][i] = temp[i][j];
ans = max(ans, sol());
// rotation
foru(i, 1, n) foru(j, 1, n) temp[i][j] = a[i][j];
foru(i, 1, n) foru(j, 1, n) a[n - j + 1][i] = temp[i][j];
ans = max(ans, sol());
return ans;
}
#ifdef testing
int main()
{
if (fopen("01.in", "r")) {
freopen("01.in", "r", stdin);
freopen("01.out", "w", stdout);
}
int N;
assert(1 == scanf("%d", &N));
std::vector<std::vector<int>> F(N, std::vector<int>(N));
for (int i = 0; i < N; i++)
{
for (int j = 0; j < N; j++)
{
assert(1 == scanf("%d", &F[i][j]));
}
}
fclose(stdin);
int res = biggest_stadium(N, F);
printf("%d\n", res);
fclose(stdout);
return 0;
}
#endif
