Submission #855862

#	Time	Username	Problem	Language	Result	Execution time	Memory
855862		abcvuitunggio	The Kingdom of JOIOI (JOI17_joioi)	C++17	0 / 100	63 ms	33624 KiB

joioi

#include <bits/stdc++.h>
using namespace std;
int h,w,a[2001][2001],s[2001][2001][2],mn[2001][2],mx[2001][2],lo=1e9,hi;
bool check(int x){
    memset(s,0,sizeof(s));
    for (int i=1;i<=h;i++){
        mx[i][0]=mx[i][1]=-1;
        mn[i][0]=mn[i][1]=1e9;
        for (int j=1;j<=w;j++){
            if (a[i][j]>lo+x&&a[i][j]<hi-x)
                return false;
            for (int k=0;k<2;k++)
                s[i][j][k]=s[i][j-1][k]+s[i-1][j][k]-s[i-1][j-1][k];
            if (a[i][j]>=hi-x&&a[i][j]<=lo+x)
                continue;
            int val=(a[i][j]>=hi-x);
            s[i][j][val]++;
            mx[i][val]=max(mx[i][val],j);
            mn[i][val]=min(mn[i][val],j);
        }
    }
    for (int k=0;k<2;k++)
        for (int i=1;i<=h;i++){
            int p=1e9,q=-1;
            for (int j=i;j<=h;j++){
                p=min(p,mn[j][k]);
                q=max(q,mx[j][k]);
                if (q==-1)
                    continue;
                if ((s[i][q][k^1]-s[0][q][k^1]-s[i][p-1][k^1]+s[0][p-1][k^1])&&(s[h][q][k^1]-s[j-1][q][k^1]-s[h][p-1][k^1]+s[j-1][p-1][k^1]))
                    return false;
            }
        }
    return true;
}
int main(){
    ios_base::sync_with_stdio(NULL);cin.tie(nullptr);
    cin >> h >> w;
    for (int i=1;i<=h;i++)
        for (int j=1;j<=w;j++){
            cin >> a[i][j];
            lo=min(lo,a[i][j]);
            hi=max(hi,a[i][j]);
        }
    int l=0,r=1e9,kq=-1;
    while (l<=r){
        int mid=(l+r)>>1;
        if (check(mid)){
            kq=mid;
            r=mid-1;
        }
        else
            l=mid+1;
    }
    cout << kq;
}

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