Submission #204172

#	Time	Username	Problem	Language	Result	Execution time	Memory
204172		mdn2002	The Kingdom of JOIOI (JOI17_joioi)	C++14	0 / 100	5 ms	380 KiB

joioi

#include<bits/stdc++.h>
using namespace std;
const long long mod=998244353;
int xx[]={1,-1,0,0},yy[]={0,0,1,-1};
long long n,m,a[2050][2050],on[2050],of[2050],ans=1e18;
multiset<pair<long long,pair<int,int> > >ms;
multiset<long long>s,s1;
bool vis[2050][2050];
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    //freopen(".in","r",stdin);
    //freopen(".out","w",stdout);
    cin>>n>>m;
    for(int i=0;i<n;i++)
    {
        for(int j=0;j<m;j++)
        {
            cin>>a[i][j];
            if(i==0||j==0||i==n-1||j==m-1)ms.insert({a[i][j],{i,j}});
            s.insert(a[i][j]);
        }
    }
    pair<long long,pair<int,int> >z=*--ms.end();
    s.erase(s.lower_bound(z.first));
    ans=min(ans,*--s.end()-*s.begin());
    s1.insert(z.first);
    ms.clear();
    int x=z.second.first,y=z.second.second;
    vis[x][y]=1;
    on[x]=1,of[y]=1;
    for(int i=0;i<4;i++)
    {
        int tx=x+xx[i],ty=y+yy[i];
        if(0<=tx&&tx<n&&0<=ty&&ty<m)ms.insert({a[tx][ty],{tx,ty}});
    }
    while(s.size()>1)
    {
        pair<long long,pair<int,int> >z=*--ms.end();
        ms.erase(--ms.end());
        long long val=z.first,x=z.second.first,y=z.second.second;
        if(vis[x][y])continue;
        if(on[x]&&vis[x][y-1]==0&&vis[x][y+1]==0)continue;
        if(of[y]&&vis[x-1][y]==0&&vis[x+1][y]==0)continue;
        vis[x][y]=1;
        s.erase(s.lower_bound(val));
        s1.insert(val);
        long long dif=max(*--s1.end()-*s1.begin(),*--s.end()-*s.begin());
        ans=min(ans,dif);
        on[x]=1,of[y]=1;
        for(int i=0;i<4;i++)
        {
            int tx=x+xx[i],ty=y+yy[i];
            if(vis[tx][ty])continue;
            if(0<=tx&&tx<n&&0<=ty&&ty<m)
            {
                if(i<2)
                {
                    if(on[tx]==0)ms.insert({a[tx][ty],{tx,ty}});
                    else if(vis[tx][ty-1]||vis[tx][ty+1])ms.insert({a[tx][ty],{tx,ty}});
                }
                if(2<=i)
                {
                    if(of[ty]==0)ms.insert({a[tx][ty],{tx,ty}});
                    else if(vis[tx-1][ty]||vis[tx+1][ty])ms.insert({a[tx][ty],{tx,ty}});
                }
            }
        }
    }
    cout<<ans<<endl;
}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 45
• Subtask 3: 0 / 40