#include "soccer.h"
#include <bits/stdc++.h>
using namespace std;
const int mxn=2006;
int ans,dp[mxn][mxn][2],l[mxn][mxn],u[mxn][mxn],d[mxn][mxn],r[mxn][mxn];
vector <int> ve[mxn][mxn];
int f(int i, int j, int b){
if (dp[i][j][b]!=-1)
return dp[i][j][b];
dp[i][j][b]=0;
int sz=j-l[i][j]+1;
for (int k:ve[i][j]){
if (l[k][j]==l[i][j]&&((k>i)^b))
continue;
dp[i][j][b]=max(dp[i][j][b],f(k,j,(k>i))-sz*(d[k][j]-u[k][j]+1));
}
if (r[i][j])
dp[i][j][b]=max(dp[i][j][b],max(f(i,j+1,0),f(i,j+1,1))-sz*(d[i][j+1]-u[i][j+1]+1));
dp[i][j][b]+=sz*(d[i][j]-u[i][j]+1);
return dp[i][j][b];
}
int biggest_stadium(int n, vector <vector <int>> F){
for (int i=0;i<n;i++)
for (int j=0;j<n;j++){
l[i][j]=(j&&!F[i][j-1]?l[i][j-1]:j);
r[i][j]=(j<n-1&&!F[i][j+1]);
d[i][j]=n-1;
}
for (int j=0;j<n;j++){
stack <int> st;
for (int i=0;i<n;i++){
while (!st.empty()&&(F[i][j]||l[i][j]>l[st.top()][j])){
d[st.top()][j]=i-1;
st.pop();
}
if (!st.empty())
ve[st.top()][j].push_back(i);
if (!F[i][j])
st.push(i);
}
while (!st.empty())
st.pop();
for (int i=n-1;i>=0;i--){
while (!st.empty()&&(F[i][j]||l[i][j]>l[st.top()][j])){
u[st.top()][j]=i+1;
st.pop();
}
if (!st.empty())
ve[st.top()][j].push_back(i);
if (!F[i][j])
st.push(i);
}
}
memset(dp,-1,sizeof(dp));
for (int i=0;i<n;i++)
for (int j=0;j<n;j++)
if (!F[i][j])
ans=max(ans,max(f(i,j,0),f(i,j,1)));
return ans;
}
