Submission #1181632

#	Time	Username	Problem	Language	Result	Execution time	Memory
1181632		MongHwa	The Kingdom of JOIOI (JOI17_joioi)	C++20	0 / 100	0 ms	324 KiB

joioi

#pragma GCC optimize ("Ofast")
#pragma GCC optimize ("unroll-loops")
#include <iostream>
using namespace std;

#define INF 0x7f7f7f7f

int stage[2005][2005];
int val[2005], bound[2005];

bool solve(int H, int W, int aval, int bval, int target)
{
    for(int j = 0; j < W; j++)
    {
        val[j] = H;
        for(int i = H-1; i >= 0; i--)
        {
            if(abs(aval-stage[i][j]) <= target)
                val[j] = i;
            else
                break;
        }
    }

    bool ret = 1;
    for(int j = 0; j < W; j++)
    {
        bound[j] = -1;
        for(int i = 0; i < H; i++)
        {
            if(abs(bval-stage[i][j]) <= target)
            {
                if(i >= val[j]-1)
                    bound[j] = i;
            }
            else
                break;
        }

        if(bound[j] == -1)
            return false;
    }

    return true;
}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);

    int H, W;
    cin >> H >> W;

    int mn = INF, mx = 0;
    for(int i = 0; i < H; i++)
        for(int j = 0; j < W; j++)
        {
            cin >> stage[i][j];
            mn = min(mn, stage[i][j]);
            mx = max(mx, stage[i][j]);
        }
    
    int l = 0, r = mx-mn;
    while(l < r)
    {
        int mid = (l+r) / 2;

        if(solve(H, W, mn, mx, mid) || solve(H, W, mx, mn, mid))
            r = mid;
        else
            l = mid+1;
    }

    cout << l << '\n';
}

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