#include <bits/stdc++.h>
#define f first
#define s second
#define ent '\n'
typedef long long ll;
using namespace std;
struct seg{
int m1,m2,sum,cnt;
};
const string out[2]={"NO\n","YES\n"};
const ll dx[]={0,1,0,-1,-1,1,1,-1};
const ll dy[]={1,0,-1,0,-1,1,-1,1};
const int mod=998244353;
const int md=1e9+7;
const int mx=2e3+12;
const bool T=0;
int ptr[512][512][512];
int dp[512][512][512];
int pref[512][512];
int n;
int get(int i,int l,int r){
if(!l)return pref[i][r];
return pref[i][r]-pref[i][l-1];
}
int biggest_stadium(int N, vector<vector<int>> a) {
n = N;
if (n > 500) {
return 0;
}
for(int i=0;i<n;i++){
for(int j=0;j<n;j++){
pref[i][j]=a[i][j];
if(j) pref[i][j]+=pref[i][j-1];
}
}
for(int i=0;i<=n;i++){
for(int j=0;j<=n;j++){
for(int k=0;k<=n;k++){
ptr[i][j][k]=-1;
dp[i][j][k]=-1e9;
}
}
}
int ans=0;
for(int l=0;l<n;l++){
for(int r=l;r<n;r++){
for(int i=0;i<n;i++){
if(get(i,l,r)){
continue;
}
int j=i;
while(j<n-1 && !get(j+1,l,r)){
j++;
}
ptr[i][l][r]=j;
i=j;
}
}
}
for(int len=n;len>=1;len--){
for(int l=0;l+len-1<n;l++){
int r=l+len-1;
for(int i=0;i<n;i++){
if(ptr[i][l][r]==-1){
continue;
}
int j=ptr[i][l][r];
dp[i][l][r]=(j-i+1)*(r-l+1);
for(int s=i;s<=j;s++) {
if(l>0 && ptr[s][l-1][r]!=-1){
int t=ptr[s][l-1][r];
dp[i][l][r]=max(dp[i][l][r], dp[s][l-1][r] + ((j-i+1) - (t-s+1)) * (r-l+1));
}
if(r<n-1 && ptr[s][l][r+1]!=-1){
int t=ptr[s][l][r+1];
dp[i][l][r]=max(dp[i][l][r], dp[s][l][r+1] + ((j-i+1) - (t-s+1)) * (r-l+1));
}
}
ans=max(ans,dp[i][l][r]);
i=j;
}x`
}
}
return ans;
}
Compilation message
soccer.cpp:89:15: error: stray '`' in program
89 | }x`
| ^
soccer.cpp: In function 'int biggest_stadium(int, std::vector<std::vector<int> >)':
soccer.cpp:89:14: error: 'x' was not declared in this scope
89 | }x`
| ^