제출 #80973

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
80973		inom	Chessboard (IZhO18_chessboard)	C++14	70 / 100	748 ms	61344 KiB

chessboard

#include <bits/stdc++.h>
 
#define fi first
#define se second
#define pb push_back
#define int long long
#define sz(c) (int)(c).size()
#define all(c) (c).begin(), (c).end()
#define in freopen("A.in", "r", stdin);
#define out freopen("A.out", "w", stdout);

using namespace std;
  
const int N = 500500;
const int INF = 1e15;

int TN = 1;

int n, k, ans = INF;
pair<int, int> a[N];

int get(int a, int b, int c) {
    a--; b--;
    a /= c; b /= c;
    a++; b++;
    return a + b;
}

int calc(int x) {
    if (x == n) {
        return INF;
    }
    // если первая фигня должна быть белой;
    int res = (((n / x) * (n / x)) / 2) * x * x;
    for (int i = 1; i <= k; i++) {
        if (get(a[i].fi, a[i].se, x) % 2 == 0) {
            res++;
        }
        else {
            res--;
        }
    }
    // иначе;
    int tmp = (((n / x) * (n / x)) / 2 + (n / x) % 2) * x * x;
    for (int i = 1; i <= k; i++) {
        if (get(a[i].fi, a[i].se, x) % 2 == 0) {
            tmp--;
        }
        else {
            tmp++;
        }
    }
    return min(res, tmp);
}

void solve() {
    cin >> n >> k;
    for (int i = 1; i <= k; i++) {
        cin >> a[i].fi >> a[i].se >> a[i].fi >> a[i].se;
    }
    for (int i = 1; i * i <= n; i++) {
        if (n % i == 0) {
            if (i * i == n) {
                ans = min(ans, calc(i));
            }
            else {
                ans = min(ans, calc(i));
                ans = min(ans, calc(n / i));
            }
        }
    }
    cout << ans << "\n";
    return;
}

signed main() {
    // ios_base::sync_with_stdio(0);
    // in; out; // cin >> TN;
    while (TN--) solve();
    return 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