Submission #747102

#	Time	Username	Problem	Language	Result	Execution time	Memory
747102		heeheeheehaaw	Chessboard (IZhO18_chessboard)	C++17	70 / 100	504 ms	4388 KiB

chessboard

#include <iostream>
#include <vector>
#define int long long

using namespace std;

int a[1005][1005];
int spw[1005][1005], spb[1005][1005];
int x1[100005], x2[100005], y1[100005], y2[100005];

void add(int x, int y, int val, int &s1, int &s2)
{
    if((int)(x + y) % 2 == 0)
        s1 += val;
    else
        s2 += val;
    return;
}

signed main()
{
    int s1 = 0, s2 = 0;
    int n, k;
    cin>>n>>k;

    vector<int> divs;
    for(int i = 1; i * i <= n; i++)
        if(n % i == 0)
        {
            divs.push_back(i);
            if(i * i != n && i != 1)
                divs.push_back(n / i);
        }

    for(int i = 1; i <= k; i++)
        cin>>x1[i]>>y1[i]>>x2[i]>>y2[i];

    int minn = n * n;
    for(auto d : divs)
    {
        int s1 = 0, s2 = 0;
        for(int i = 1; i <= k; i++)
        {
            int cx1 = (int)(x1[i] - 1) / d + 1;
            int cy1 = (int)(y1[i] - 1) / d + 1;
            int cx2 = (int)(x2[i] - 1) / d + 1;
            int cy2 = (int)(y2[i] - 1) / d + 1;

            if(cx1 == cx2 && cy1 == cy2)
            {
                int tt = (x2[i] - x1[i] + 1) * (y2[i] - y1[i] + 1);
                add(cx1, cy1, tt, s1, s2);
            }
            else if(cx1 == cx2 && cy1 != cy2)
            {
                /// colt stanga
                int tt = ((d * cy1) - y1[i] + 1) * (x2[i] - x1[i] + 1);
                add(cx1, cy1, tt, s1, s2);
                /// colt dreapta
                    tt = (y2[i] - d * (cy2 - 1)) * (x2[i] - x1[i] + 1);
                add(cx2, cy2, tt, s1, s2);
                /// mijloc
                if(cy2 - cy1 - 1 >= 1)
                {
                    int tt = d * (x2[i] - x1[i] + 1);
                    int np = cy2 - cy1 - 1;
                    int nri = np / 2, nrp = np / 2;
                    if(np % 2 == 1)
                        nri++;
                    add(cx1, cy1 + 1, tt * nri, s1, s2);
                    add(cx1, cy1 + 2, tt * nrp, s1, s2);
                }
            }
            else if(cx1 != cx2 && cy1 == cy2)
            {
                /// colt sus
                int tt = ((d * cx1) - x1[i] + 1) * (y2[i] - y1[i] + 1);
                add(cx1, cy1, tt, s1, s2);
                /// colt jos
                    tt = (x2[i] - d * (cx2 - 1)) * (y2[i] - y1[i] + 1);
                add(cx2, cy2, tt, s1, s2);
                /// mijloc
                if(cx2 - cx1 - 1 >= 1)
                {
                    int tt = d * (y2[i] - y1[i] + 1);
                    int np = cx2 - cx1 - 1;
                    int nri = np / 2, nrp = np / 2;
                    if(np % 2 == 1)
                        nri++;
                    add(cx1 + 1, cy1, tt * nri, s1, s2);
                    add(cx1 + 2, cy1, tt * nrp, s1, s2);
                }
            }
            else
            {
                /// colt st sus
                int tt = (d * cx1 - x1[i] + 1) * (d * cy1 - y1[i] + 1);
                add(cx1, cy1, tt, s1, s2);
                /// colt dr sus
                    tt = (d * cx1 - x1[i] + 1) * (y2[i] - d * (cy2 - 1));
                add(cx1, cy2, tt, s1, s2);
                /// colt st jos
                    tt = (x2[i] - d * (cx2 - 1)) * (d * cy1 - y1[i] + 1);
                add(cx2, cy1, tt, s1, s2);
                /// colt dr jos
                    tt = (x2[i] - d * (cx2 - 1)) * (y2[i] - d * (cy2 - 1));
                add(cx2, cy2, tt, s1, s2);
                /// marg sus si jos
                if(cy2 - cy1 - 1 >= 1)
                {
                    tt = (d * cx1 - x1[i] + 1) * d;
                    int np = cy2 - cy1 - 1;
                    int nri = np / 2, nrp = np / 2;
                    if(np % 2 == 1)
                        nri++;
                    add(cx1, cy1 + 1, tt * nri, s1, s2);
                    add(cx1, cy1 + 2, tt * nrp, s1, s2);
                    tt = (x2[i] - d * (cx2 - 1)) * d;
                    add(cx2, cy1 + 1, tt * nri, s1, s2);
                    add(cx2, cy1 + 2, tt * nrp, s1, s2);
                }
                /// marg st si dr
                if(cx2 - cx1 - 1 >= 1)
                {
                    tt = (d * cy1 - y1[i] + 1) * d;
                    int np = cx2 - cx1 - 1;
                    int nri = np / 2, nrp = np / 2;
                    if(np % 2 == 1)
                        nri++;
                    add(cx1 + 1, cy1, tt * nri, s1, s2);
                    add(cx1 + 2, cy1, tt * nrp, s1, s2);
                    tt = (y2[i] - d * (cy2 - 1)) * d;
                    add(cx1 + 1, cy2, tt * nri, s1, s2);
                    add(cx1 + 2, cy2, tt * nrp, s1, s2);
                }

                /// mijloc
                /*if((cx2 - cx1 - 1) * (cy2 - cy1 - 1) >= 1)
                {
                    int nrp = (cx2 - cx1 - 1) * (cy2 - cy1 - 1);
                    int d1 = nrp / 2, d2 = nrp / 2;
                    if(nrp % 2 == 1)
                        d1++;
                    add(cx1 + 1, cx2 + 1, d * d * d1, s1, s2);
                    add(cx1 + 1, cx2 + 2, d * d * d2, s1, s2);
                }*/
            }
        }

        int d1 = (int)n * n, d2 = (int)n * n;
        int nli = (int)n / d / 2, nlp = (int)n / d / 2;
        if((n / d) % 2 == 1) nli++;

        d2 -= (int)(d * d * (nli * nli + nlp * nlp));
        d1 = (int)n * n - d2;
        int ans = min(d1 - s1 + s2, d2 - s2 + s1);
        minn = min(minn, ans);
    }

    cout<<minn<<'\n';

    return 0;
}

Compilation message (stderr)

chessboard.cpp: In function 'int main()':
chessboard.cpp:22:9: warning: unused variable 's1' [-Wunused-variable]
   22 |     int s1 = 0, s2 = 0;
      |         ^~
chessboard.cpp:22:17: warning: unused variable 's2' [-Wunused-variable]
   22 |     int s1 = 0, s2 = 0;
      |                 ^~

• Subtask 1: 8 / 8
• Subtask 2: 8 / 8
• Subtask 3: 15 / 15
• Subtask 4: 16 / 16
• Subtask 5: 23 / 23
• Subtask 6: 0 / 30