Submission #90283

#	Time	Username	Problem	Language	Result	Execution time	Memory
90283		HardNut	Chessboard (IZhO18_chessboard)	C++17	39 / 100	66 ms	9488 KiB

chessboard

#include <bits/stdc++.h>

using namespace std;

const int N = 1e5 + 5;
const long long INF = 1e9 + 5;
const int MAXN = 1e6;
const int base = 317;

typedef long long ll;

const ll bs = 1e5 + 1;
const ll mod = 998244353;

int ans = INF, n, k, xx[N], yy[N];

int calc(int x) {
    int res1 = 0, res2 = 0;
    for (int i = 1; i <= k; i++) {
        if ((xx[i] / x) % 2 == (yy[i] / x) % 2) {
            res1++;
        } else {
            res2++;
        }
    }
    int c1 = (n / x) * (n / x) / 2 * x * x;
    int c2 = n * n - c1;
    return min(c1 - res2 + res1, c2 - res1 + res2);
}

main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> k;
    for (int i = 1; i <= k; i++) {
        cin >> xx[i] >> yy[i] >> xx[i] >> yy[i];
        xx[i]--;
        yy[i]--;
    }
    for (int i = 1; i <= sqrt(n); i++) {
        if (n % i == 0) {
            ans = min(ans, calc(i));
            if (i != 1)
                ans = min(ans, calc(n / i));
        }
    }
    cout << ans;
    return 0;
}
/*

*/

Compilation message (stderr)

chessboard.cpp:31:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^

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