#pragma GCC optimize("Ofast")
#include <bits/stdc++.h>
#define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
using namespace std;
typedef long long ll;
#define int ll
const int N = 1e5 + 5;
const ll INF = 1e18;
const int mod = 1e9 + 7;
const double PI = acos(-1.0);
int n, k;
ll ans = INF;
vector < int > v;
int get(int x1, int y1, int d) {
x1 /= d;
y1 /= d;
return ((x1 % 2) == (y1 % 2));
}
int x[N], y[N];
int main() {
cin >> n >> k;
for (int i = 1; i <= k; ++i) {
int x2, y2;
cin >> x[i] >> y[i] >> x2 >> y2;
}
v.push_back(1);
for (int i = 2; i * i <= n; ++i) {
if (n % i == 0) {
v.push_back(i);
if (n / i != i) {
v.push_back(n / i);
}
}
}
for (int i : v) {
int m = n / i, cnt_black = 0, cnt_white = 0;
ll black = (((m * m) / 2) + (m * m) % 2) * (i * 1ll * i);
ll white = (n * 1ll * n) - black;
for (int j = 1; j <= k; ++j) {
cnt_black += get(x[j] - 1, y[j] - 1, i);
}
cnt_white = k - cnt_black;
ll x = (black - cnt_black) + cnt_white;
ll y = (white - cnt_white) + cnt_black;
ans = min(ans, min(x, y));
}
cout << ans;
}
Compilation message
chessboard.cpp:30:10: error: '::main' must return 'int'
int main() {
^
