#include <bits/stdc++.h>
using namespace std;
bool limites(int N, int i, int j){
return i>=0&&i<N&&j>=0&&j<N;
}
bool comprobar(int N, vector<vector<int>> F){
for(int i=0;i<N;i++){
for(int j=0;j<N;j++){
if(F[i][j]==1){
continue;
}
priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>,greater<tuple<int,int,int>>>cola;
int dx[]={1,0,-1,0};
int dy[]={0,1,0,-1};
vector<vector<int>>dist(N,vector<int>(N,INT_MAX));
dist[i][j]=0;
cola.push({0,i,j});
while(!cola.empty()){
auto[d,x,y]=cola.top();
cola.pop();
for(int dir=0;dir<4;dir++){
int posi=x+dx[dir];
int posj=y+dy[dir];
while(true){
if(!limites(N,posi,posj)||F[posi][posj]==1)break;
if((d+1)<dist[posi][posj]){
dist[posi][posj]=d+1;
cola.push({dist[posi][posj],posi,posj});
}
posi+=dx[dir];
posj+=dy[dir];
}
}
}
for(int x=0;x<N;x++){
for(int y=0;y<N;y++){
if(F[x][y]==0&&(dist[x][y]>=3||dist[x][y]==-1)){
return false;
}
}
}
}
}
return true;
}
int biggest_stadium(int N, vector<vector<int>> F){
int si_hay_arbol=0;
pair<int,int>arbol;
for(int i=0;i<N;i++){
for(int j=0;j<N;j++){
if(F[i][j]==0){
continue;
}
else{
arbol={i,j};
si_hay_arbol++;
}
}
}
if(!si_hay_arbol){
return N*N;
}
else if(si_hay_arbol==1){
int a=((arbol.first+1)*(arbol.second+1))+min((arbol.first+1),(arbol.second+1));
int b=(((arbol.first+1)*(N-arbol.second))+min((arbol.first+1),(N-arbol.second)));
int c=(((N-arbol.first)*(arbol.second+1))+min((N-arbol.first),(arbol.second+1)));
int d=(((N-arbol.first)*(N-arbol.second))+min((N-arbol.first),(N-arbol.second)));
int e=((arbol.first+1)*(arbol.second+1));
int f=(((arbol.first+1)*(N-arbol.second)));
int g=(((N-arbol.first)*(arbol.second+1)));
int h=(((N-arbol.first)*(N-arbol.second)));
int max_rectangle=min(min(a,b),min(c,d));
max_rectangle=min(max_rectangle,min(min(e,f),min(g,h)));
return (N*N)-max_rectangle;
}
else if(N<=7){
int n = N;
vector<vector<int>> a = F, next(n, vector<int>(n)), sum(n, vector<int>(n));
function<int(int, int, int, int)> summ = [&] (int l, int r, int x, int y) {
long long ans = sum[y][r];
if (x - 1 >= 0) ans -= sum[x - 1][r];
if (l - 1 >= 0) ans -= sum[y][l - 1];
if (x - 1 >= 0 && l - 1 >= 0) ans += sum[x - 1][l - 1];
return ans;
};
function<int(int, int, int, int)> f = [&] (int l, int r, int x, int y) {
int ans = 0;
if (x - 1 >= 0) {
for (int j = l; j <= r; j ++) {
if (a[x - 1][j]) continue;
int z = min(r, next[x - 1][j]);
ans = max(ans, f(j, z, x - 1, y) + z - j + 1);
j = z;
}
}
if (y + 1 < n) {
for (int j = l; j <= r; j ++) {
if (a[y + 1][j]) continue;
int z = min(r, next[y + 1][j]);
int ll = y + 1, rr = n, mid;
while (ll < rr) {
mid = (ll + rr) / 2;
if (summ(j, z, x, mid) == 0) ll = mid + 1;
else rr = mid;
}
ll --;
ans = max(ans, f(j, z, x, ll) + (z - j + 1) * (ll - y));
j = z;
}
}
return ans;
};
for (int i = 0; i < n; i ++) {
for (int j = 0; j < n; j ++) {
sum[i][j] += a[i][j];
if (j) sum[i][j] += sum[i][j - 1];
}
}
for (int i = 1; i < n; i ++) {
for (int j = 0; j < n; j ++) sum[i][j] += sum[i - 1][j];
}
for (int i = 0; i < n; i ++) {
if (a[i][n - 1] == 0) next[i][n - 1] = n - 1;
else next[i][n - 1] = n - 2;
for (int j = n - 2; j >= 0; j --) {
if (a[i][j]) next[i][j] = j - 1;
else next[i][j] = next[i][j + 1];
}
}
int ans = 0;
for (int i = 0; i < n; i ++) {
for (int j = 0; j < n; j ++) {
if (a[i][j]) continue;
ans = max(ans, f(j, next[i][j], i, i) + next[i][j] - j + 1);
j = next[i][j];
}
}
return ans;
}
else{
int empty_cells=0;
for(int i=0;i<N;i++){
for(int j=0;j<N;j++){
if(F[i][j]==0){
empty_cells++;
}
}
}
bool si=true;
for(int i=0;i<N;i++){
for(int j=0;j<N;j++){
if(F[i][j]==1){
continue;
}
priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>,greater<tuple<int,int,int>>>cola;
int dx[]={1,0,-1,0};
int dy[]={0,1,0,-1};
vector<vector<int>>dist(N,vector<int>(N,INT_MAX));
dist[i][j]=0;
cola.push({0,i,j});
while(!cola.empty()){
auto[d,x,y]=cola.top();
cola.pop();
for(int dir=0;dir<4;dir++){
int posi=x+dx[dir];
int posj=y+dy[dir];
while(true){
if(!limites(N,posi,posj)||F[posi][posj]==1)break;
if((d+1)<dist[posi][posj]){
dist[posi][posj]=d+1;
cola.push({dist[posi][posj],posi,posj});
}
posi+=dx[dir];
posj+=dy[dir];
}
}
}
for(int x=0;x<N;x++){
for(int y=0;y<N;y++){
if(F[x][y]==0&&(dist[x][y]>=3||dist[x][y]==-1)){
si=false;
}
}
}
if(!si){
break;
}
}
if(!si){
break;
}
}
if(si){
return empty_cells;
}
else{
return 1;
}
}
}
