Submission #930087

#	Time	Username	Problem	Language	Result	Execution time	Memory
930087		abcvuitunggio	Soccer Stadium (IOI23_soccer)	C++17	100 / 100	799 ms	161876 KiB

soccer

#include "soccer.h"
#include <bits/stdc++.h>
using namespace std;
const int mxn=2006;
int ans,dp[mxn][mxn],l[mxn][mxn],u[mxn][mxn],d[mxn][mxn],r[mxn][mxn],L[mxn],R[mxn],h[mxn][mxn],w[mxn][mxn],a[mxn][mxn];
vector <int> ve[mxn];
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=n-1;j>=0;j--){
        stack <int> st;
        for (int i=0;i<n;i++){
            if (!F[i][j])
                ve[l[i][j]].push_back(i);
            while (!st.empty()&&(F[i][j]||l[i][j]>l[st.top()][j])){
                d[st.top()][j]=i-1;
                st.pop();
            }
            L[i]=(st.empty()?-1:st.top());
            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();
            }
            R[i]=(st.empty()?-1:st.top());
            if (!F[i][j])
                st.push(i);
        }
        for (int i=0;i<n;i++){
            h[i][j]=d[i][j]-u[i][j]+1;
            w[i][j]=j-l[i][j]+1;
            a[i][j]=w[i][j]*h[i][j];
            if (r[i][j])
                dp[i][j]=max(dp[i][j+1]-w[i][j]*h[i][j+1],0);
            dp[i][j]+=a[i][j];
        }
        for (int k=0;k<=j;k++)
            for (int it=0;it<2;it++){
                reverse(ve[k].begin(),ve[k].end());
                for (int i:ve[k])
                    if (L[i]>=0)
                        dp[L[i]][j]=max(dp[L[i]][j],dp[i][j]-w[L[i]][j]*h[i][j]+a[L[i]][j]);
                reverse(ve[k].begin(),ve[k].end());
                for (int i:ve[k])
                    if (R[i]>=0)
                        dp[R[i]][j]=max(dp[R[i]][j],dp[i][j]-w[R[i]][j]*h[i][j]+a[R[i]][j]);
            }
        for (int i=0;i<n;i++)
            ve[l[i][j]].clear();
    }
    for (int i=0;i<n;i++)
        for (int j=0;j<n;j++)
            if (!F[i][j])
                ans=max(ans,dp[i][j]);
    return ans;
}

• Subtask 0: 0 / 0
• Subtask 1: 6 / 6
• Subtask 2: 8 / 8
• Subtask 3: 22 / 22
• Subtask 4: 18 / 18
• Subtask 5: 16 / 16
• Subtask 6: 30 / 30