Submission #842470

#	Time	Username	Problem	Language	Result	Execution time	Memory
842470		firewater	Soccer Stadium (IOI23_soccer)	C++17	70 / 100	4599 ms	177372 KiB

soccer

#include "soccer.h"
#include<bits/stdc++.h>
#define fs first
#define sn second
#define mp make_pair
#define MX 2023
using namespace std;
int n,now,num,ans,sl,sr,l,r,lst[MX],nxt[MX],a[MX][MX],sum[MX][MX],stl[MX][20],str[MX][20],fl[MX][MX],fr[MX][MX];
pair<int,pair<int,int> >f[MX][MX],sav;
pair<int,int> d[MX][MX];
int dd[MX];
int getl(int l,int r)
{
    int k=__lg(r-l+1);
    return min(stl[l][k],stl[r-(1<<k)+1][k]);
}
int getr(int l,int r)
{
    int k=__lg(r-l+1);
    return min(str[l][k],str[r-(1<<k)+1][k]);
}
int biggest_stadium(int N, std::vector<std::vector<int>> F)
{
    n=N;

    for(int i=1;i<=n;++i)
        for(int j=1;j<=n;++j){
            a[i][j]=F[i-1][j-1];
            sum[i][j]=sum[i][j-1]+a[i][j];
        }
    for(int i=1;i<=n;++i){
        now=1;
        for(int j=1;j<=n;++j){
            if(a[i][j])now=j+1;
            else fl[i][j]=j-now+1;
        }
        now=n;
        for(int j=n;j>0;--j){
            if(a[i][j])now=j-1;
            else fr[i][j]=now-j+1;
        }
    }
    for(int j=1;j<=n;++j){
        for(int i=1;i<=n;++i){
            stl[i][0]=fl[i][j];
            str[i][0]=fr[i][j];
        }
        for(int k=1;k<=11;++k){
            for(int i=1;i<=n;++i){
                stl[i][k]=min(stl[i][k-1],(i+(1<<k-1)<=n?stl[i+(1<<k-1)][k-1]:n));
                str[i][k]=min(str[i][k-1],(i+(1<<k-1)<=n?str[i+(1<<k-1)][k-1]:n));
            }
        }
        for(int i=1;i<=n;++i)
            dd[i]=0;
        lst[1]=1;
        for(int i=2;i<=n;++i){
            if(fl[i][j]==fl[i-1][j]&&fr[i][j]==fr[i-1][j])lst[i]=lst[i-1];
            else lst[i]=i;
        }
        nxt[n]=n;
        for(int i=n-1;i>0;--i){
            if(fl[i][j]==fl[i+1][j]&&fr[i][j]==fr[i+1][j])nxt[i]=nxt[i+1];
            else nxt[i]=i;
        }
        for(int i=1;i<=n;++i){
            if(i>1&&fl[i-1][j]>=fl[i][j]&&fr[i-1][j]>=fr[i][j]&&(!(fl[i-1][j]==fl[i][j]&&fr[i-1][j]==fr[i][j])))continue;
            if(i<n&&fl[i+1][j]>=fl[i][j]&&fr[i+1][j]>=fr[i][j])continue;
            f[i][i]=mp(max(0,fl[i][j]+fr[i][j]-1),mp(fl[i][j],fr[i][j]));
            d[1][++dd[1]]=(mp(i,i));
        }
        for(int len=1;len<=n;++len){
            int i,k;
            for(int g=1;g<=dd[len];++g){
                i=d[len][g].fs;k=d[len][g].sn;
                sl=f[i][k].sn.fs;
                sr=f[i][k].sn.sn;
                if(sl+sr<1)continue;
                ans=max(ans,f[i][k].fs);
                
                if(i>1&&(k==n||min(f[i][k].sn.fs,fl[i-1][j])>min(f[i][k].sn.fs,fl[k+1][j])||min(f[i][k].sn.sn,fr[i-1][j])>min(f[i][k].sn.sn,fr[k+1][j]))){
                    sl=min(f[i][k].sn.fs,fl[i-1][j]);
                    sr=min(f[i][k].sn.sn,fr[i-1][j]);
                    if(sl+sr>0){
                        l=1;r=lst[i-1];
                        while(l<r){
                            int mid=l+r>>1;
                            if(getl(mid,i-1)>=sl&&getr(mid,i-1)>=sr)r=mid;
                            else l=mid+1;
                        }
                        sav=mp(f[i][k].fs+max(sr+sl-1,0)*(i-l),mp(sl,sr));
                        if(sav.fs>0&&sav>f[l][k]){
                            if(f[l][k].fs==0)d[k-l+1][++dd[k-l+1]]=(mp(l,k));
                            f[l][k]=sav;
                        }
                    }
                }
                if(k<n&&(i==1||min(f[i][k].sn.fs,fl[k+1][j])>=min(f[i][k].sn.fs,fl[i-1][j])||min(f[i][k].sn.sn,fr[k+1][j])>min(f[i][k].sn.sn,fr[i-1][j]))){
                    sl=min(f[i][k].sn.fs,fl[k+1][j]);
                    sr=min(f[i][k].sn.sn,fr[k+1][j]);
                    if(sl+sr>0){
                        l=nxt[k+1];r=n;
                        while(l<r){
                            int mid=l+r+1>>1;
                            if(getl(k+1,mid)>=sl&&getr(k+1,mid)>=sr)l=mid;
                            else r=mid-1;
                        }
                        sav=mp(f[i][k].fs+max(sr+sl-1,0)*(l-k),mp(sl,sr));
                        if(sav.fs>0&&sav>f[i][l]){
                            if(f[i][l].fs==0)d[l-i+1][++dd[l-i+1]]=(mp(i,l));
                            f[i][l]=sav;
                        }
                    }
                }
                f[i][k]=mp(0,mp(0,0));
            }
        }
    }
    return ans;
}

Compilation message (stderr)

soccer.cpp: In function 'int biggest_stadium(int, std::vector<std::vector<int> >)':
soccer.cpp:53:51: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   53 |                 stl[i][k]=min(stl[i][k-1],(i+(1<<k-1)<=n?stl[i+(1<<k-1)][k-1]:n));
      |                                                  ~^~
soccer.cpp:53:69: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   53 |                 stl[i][k]=min(stl[i][k-1],(i+(1<<k-1)<=n?stl[i+(1<<k-1)][k-1]:n));
      |                                                                    ~^~
soccer.cpp:54:51: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   54 |                 str[i][k]=min(str[i][k-1],(i+(1<<k-1)<=n?str[i+(1<<k-1)][k-1]:n));
      |                                                  ~^~
soccer.cpp:54:69: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   54 |                 str[i][k]=min(str[i][k-1],(i+(1<<k-1)<=n?str[i+(1<<k-1)][k-1]:n));
      |                                                                    ~^~
soccer.cpp:90:38: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   90 |                             int mid=l+r>>1;
      |                                     ~^~
soccer.cpp:107:40: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
  107 |                             int mid=l+r+1>>1;
      |                                     ~~~^~

• 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: 0 / 30