Submission #598777

#	Time	Username	Problem	Language	Result	Execution time	Memory
598777		Hanksburger	The Kingdom of JOIOI (JOI17_joioi)	C++17	100 / 100	604 ms	54812 KiB

joioi

#include <bits/stdc++.h>
using namespace std;
int a[2005][2005], b[2005];
int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int n, m, mn=1e9, mx=0, ans=1e9;
    cin >> n >> m;
    for (int i=1; i<=n; i++)
    {
        for (int j=1; j<=m; j++)
        {
            cin >> a[i][j];
            mn=min(mn, a[i][j]);
            mx=max(mx, a[i][j]);
        }
    }
    b[0]=m+1;
    for (int y=2; y--; )
    {
        for (int z=2; z--; )
        {
            int l=0, r=1e9;
            while (l<r)
            {
                int mid=(l+r)/2;
                bool ok=1;
                for (int i=1; i<=n; i++)
                {
                    for (int j=1; j<=m; j++)
                    {
                        if (j==b[i-1] || a[i][j]>mn+mid)
                        {
                            b[i]=j;
                            break;
                        }
                        if (j==m)
                        {
                            b[i]=j+1;
                            break;
                        }
                    }
                    for (int j=b[i]; j<=m; j++)
                    {
                        if (a[i][j]<mx-mid)
                        {
                            ok=0;
                            break;
                        }
                    }
                    if (!ok)
                        break;
                }
                if (ok)
                    r=mid;
                else
                    l=mid+1;
            }
            ans=min(ans, l);
            for (int i=1; i<=n; i++)
                for (int j=1; j<=m/2; j++)
                    swap(a[i][j], a[i][m+1-j]);
        }
        for (int i=1; i<=m; i++)
            for (int j=1; j<=n/2; j++)
                swap(a[j][i], a[n+1-j][i]);
    }
    cout << ans;
    return 0;
}

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